Mpox Awareness and Vaccine Acceptability among Transgender Women and Men who have Sex with Men in India: Predictors and Implications for Outbreak Preparedness

Abstract

Background

Men who have sex with men (MSM) and transgender women (TGW) are at elevated mpox risk; vaccination can greatly reduce that risk. We assessed mpox awareness and vaccine acceptability among MSM and TGW.

Methods

In 2022, hybrid-mode (offline/online) surveys were administered among 250 MSM and 251 TGW in Chennai, India. Robust Poisson regression models were used to identify predictors of mpox awareness and vaccine acceptability.

Results

Participants’ mean age was 29.1; mean monthly income USD 192. Over half (54.5%) had a college/diploma degree; 29% of MSM and 90% of TGW reported engaging in sex work in the past month; and 49% of MSM and 86% of TGW reported inconsistent condom use with male partners. Overall, 59% had heard of mpox; 37% knew of its high burden among MSM/TGW. Vaccine acceptability was 36.7% (MSM: 53.6%; TGW: 19.9%). Mpox awareness was predicted by higher education (Prevalence-Rate-Ratio/PRR=1.18, p=0.04), online recruitment (PRR=1.28, p=0.01), PrEP awareness (PRR=1.30, p<0.001), and more non-regular male sexual partners (PRR=1.03 per 10-partner increment, p=0.01). Mpox vaccine acceptability was positively associated with awareness about high mpox burden among MSM/TGW (PRR=1.31, p=0.04) and online recruitment mode (PRR=1.52, p=0.001), but negatively with depression (PRR=0.68, p=0.02) and inconsistent condom use (PRR=0.68, p=0.002). TGW were less willing than MSM (PRR=0.43, p<0.001).

Conclusions

Suboptimal mpox awareness and vaccine acceptability among MSM and TGW highlight key vulnerabilities. Tailored, non-stigmatizing educational interventions delivered via community-based organisations, online platforms, and HIV services are needed to address informational and psychosocial barriers. For preparedness, enhancing equitable vaccine access and clinical vigilance may help strengthening India’s mpox response.

Introduction

Mpox, caused by a zoonotic orthopox virus, has emerged as a significant public health concern since 2002. The first global mpox outbreak in 2022 spread to over 110 countries, with more than 85,000 confirmed cases and 89 deaths reported by January 2023.^1,2 The second global outbreak emerged in Central Africa around September 2023 and was declared a Public Health Emergency of International Concern in August 2024, with over 29,000 cases and more than 800 deaths reported by September 2024.^2,3

The first global mpox outbreak disproportionally affected gay, bisexual, and other cisgender men who have sex with men (MSM) as well as transgender women (TGW).² This was attributed to factors including limited community awareness of mpox, long incubation period, characteristics of sexual networks, initial lack of vaccine access, and societal stigma related to sexuality and mpox itself.^4–6 In the first global mpox (clade IIb) outbreak, India officially reported 24 lab-confirmed mpox cases, with most of them reported to be sexually active, although none of the males reported same-sex sexual behaviour.⁷ While the 2024 resurgence linked to Clade Ib saw increased pediatric cases in Africa; India reported one adult patient with Clade IIb mpox on September 8, 2024, with a recent international travel history.⁸

In India, the response to mpox is shaped by unique social and structural factors. The legacy of criminalization of adult consensual same-sex sexual relations, pervasive societal stigma against same-sex sexuality, and gaps in legal protections continue to influence the visibility and reporting patterns of mpox cases. Surveillance of mpox transmission is further complicated by reluctance to disclose sexual behaviors, which may obscure the true burden and modes of transmission among men who have sex with men. India has not announced national mpox vaccination programs, although local production of third-generation smallpox/mpox vaccines is planned.⁹

Awareness of mpox transmission modes and vaccine willingness are crucial for controlling outbreaks in vulnerable communities, including MSM and TGW. Studies outside India indicate suboptimal mpox awareness (36.9%¹⁰ to 69.9%¹¹) and vaccine uptake among these groups. Adequate level of mpox knowledge among MSM was significantly predicted by older age, higher education, and HIV status awareness in Asian studies.^10,12,13 Mpox vaccination intentions (66.2%¹⁴ to 91.4%¹¹) and actual mpox vaccination rates (43.8% to 94.5%¹³) ranged widely. Factors associated with vaccination intentions or uptake included adequate information about mpox, multiple sexual partners and perceived risk and severity of mpox,^14,15 stronger connections to the gay or transgender communities, trust in public health agencies, knowledge of peers who have received mpox vaccination, and prior vaccination against COVID-19.^{11,14,16–18}

Studies from India have documented mpox knowledge and vaccination intentions among college students,^19,20 but not among MSM and TGW, despite warnings of potential mpox epidemics in these communities.²¹ Accordingly, to address this research gap, this study aimed to assess mpox awareness and vaccination willingness among MSM and TGW in India, and to identify associated sociodemographic and behavioral factors. By addressing this gap, this study seeks to inform public health preparedness, policy development, and targeted interventions to mitigate future mpox risks for vulnerable communities in India.

Materials and Methods

Study design

A cross-sectional hybrid-mode (offline and online) study was conducted among 250 MSM and 251 TGW in the last quarter of 2022 in Chennai, a city in South India. Offline participants (n=300) were recruited using community-based convenience sampling, where peer recruiters approached eligible participants registered with community-based organizations providing HIV prevention services. These participants completed face-to-face surveys administered by peer research interviewers using SmartPads. Online participants (n=201) were recruited through self-selected sampling, where peer recruiters contacted individuals not registered with community-based organizations through various social media platforms and dating apps (such as Facebook, Grindr, Blued and WhatsApp) where communities were active. For those recruited online, participants were given a link which directed them to a self-administered survey (Tamil and English languages). Peer research interviewers administered surveys face-to-face through SmartPads among offline participants. Eligible participants included those who were at least 18 years old, sexually active in the past two months, and who were willing to provide written informed consent. Participants were paid an honorarium of INR 500 (USD 6) for the 35- to 45-minute survey interview. The study protocol (No. 2021/521) was approved by the Institutional Review Board of Centre of Sexuality and Health Research and Policy in India.

Measures

Socio-demographics

Socio-demographic characteristics included age, education, occupation, personal monthly income, current relationship status, and self-reported sexual or sexual role-based identities among MSM: gay, bisexual, kothi (feminine/receptive role), double-decker (insertive and receptive roles), or panthi (masculine/insertive);²² and self-reported gender identities, including indigenous transgender identities, among TGW (e.g., thirunangai, hijra, kinnar).

HIV/STI risk behavior and vaccination history

HIV and STI risk behavior measures assessed: whether participants engaged in sex work in the past month, the number of regular or non-regular male sexual partners and consistency of condom use with male partners (past 2 months) (“How often have you used condoms when you had anal sex with regular or non-regular male partners in the past 2 months?”), prevalence of any clinician-diagnosed STIs (During the past 3 months, has a doctor or nurse told you that you had a sexually transmitted disease [such as Syphilis, Herpes, Gonorrhea, Chlamydia, or Genital warts]? – yes or no), HIV testing and current HIV status, and awareness of HIV pre-exposure prophylaxis (PrEP) (“Before this interview, have you heard of or read about taking daily oral pills called PrEP to prevent HIV?”). Additionally, the status of COVID-19 vaccination (completed two doses – yes or no) and Hepatitis B vaccination (completed 3-dose schedule – yes or no) was assessed.

Psychosocial health conditions

Depression

A 9-item Patient Health Questionnaire (PHQ-9) was used to evaluate the presence of depressive symptoms during the past 2 weeks.²³Sample item: “Little interest or pleasure in doing things”. Each item was answered with a score of 0 for ‘Not at all’ to 3 for ‘Nearly every day’. The total score was used as a measure of depressive symptom severity, with higher scores indicating higher levels of depression (range: 0-27). A PHQ-9 total score of ≥5 was considered indicative of depressive symptoms. The Cronbach’s alpha of this scale was 0.81.

Anxiety

A two-item Generalized Anxiety Disorder-2 (GAD-2) scale measured anxiety experience in the past two weeks.²⁴ The items were: 1) “Feeling nervous, anxious, or on edge” and 2) “Not being able to stop or control worrying”, with scores ranging from 0 (not at all) to 3 (nearly every day) for each item. The total score range was 0-6. A GAD total score of ≥2 was considered indicative of anxiety symptoms. The Cronbach’s alpha of this scale was 0.84.

Awareness of mpox

Each participant was asked two questions on mpox awareness: 1) Previous knowledge about mpox: “Have you heard of or read about Monkeypox (Mpox)?”, and 2) Awareness of disproportionate burden among MSM/TGW: “Most of the persons who have contracted mpox were reported to be men who have sex with men. It has also been reported among transgender persons. Are you aware of this?”. The response options were ‘yes’ or ‘no’.

Mpox vaccine acceptability

Willingness to use the mpox vaccine was assessed by asking: “If a single-dose vaccine is available to prevent mpox, are you willing to take it?”. The response options were presented on a 5-point Likert-type scale (1=‘Yes, definitely’, 2=‘Yes, probably’, 3=‘Not sure’, 4=‘No, probably not’, 5=‘No, definitely not’). These responses were then dichotomized into “Yes” (option 1) and “No” (combining options 2 to 5) for the analysis. This conservative dichotomization approach was chosen to identify individuals with strong, unambiguous vaccine intentions who would be most likely to receive vaccination when available and to align with public health planning needs that require conservative estimates for predicting vaccine demand.

Statistical analysis

Descriptive statistics were calculated for sociodemographic characteristics, HIV/STI risk behaviors, psychosocial problems (anxiety and depression), awareness of mpox and willingness to use mpox vaccines. Multivariable Poisson regression models using robust standard errors were fitted to examine the association between the predictors and two binary outcomes – awareness of mpox and mpox vaccine acceptability – to estimate Prevalence Rate Ratios (PRRs) and 95% confidence intervals (CIs). Although the outcomes were binary, Poisson regression models with robust error variance were chosen over logistic regression models because the outcomes were common (>10%) and PRRs are more interpretable and easier to understand than odds ratios.^25,26 PRRs represent the ratio of the prevalence of the outcome in participants with a specific characteristic compared to those without that characteristic (i.e., reference group), with values >1 indicating higher prevalence and values <1 indicating lower prevalence. Age, education, gender, number of sexual partners, condom use, sex work engagement in the past month, PrEP awareness and mode of recruitment (online/offline) were the predictors included in the regression models for both outcomes (mpox awareness and mpox vaccine acceptability), based on prior literature and hypothesized confounding associations. Mpox awareness, anxiety, depression, and COVID-19 vaccination status were the additional predictors or covariates included in the regression models for mpox vaccine acceptability. We used goodness-of-fit tests to assess the fit of Poisson models (Stata-18 post-estimation command: estat gof). Listwise deletion was used to handle missing data. All analyses were performed using Stata-18.²⁷

Results

Participant Characteristics

Table 1 describes socio-demographic and behavioral characteristics of the study participants (MSM=250; TGW=251). Participants’ mean age was 29.13 (SD 6.28) and the mean monthly personal income was INR 15332 (USD 192).

Table 1. Sociodemographic and behavioral characteristics of the participants (n=501).

	Overall n=501	MSM N=250	TGW N=251	pa
	n (%)	n (%)	n (%)
Sociodemographics
Age (years)	29.1 (6.2)	29.5 (6.8)	28.8 (5.7)	0.19
Personal monthly income (INR)	15332 (8912)	15566 (11691)	15109 (4979)	0.57
Occupation
Unemployed	31 (6.2)	20 (8.0)	11 (4.4)
Student	18 (3.6)	16 (6.4)	2 (0.8)
Daily-wage laborer	22 (4.4)	19 (7.6)	3 (1.2)
Government staff	3 (0.6)	2 (0.8)	1 (0.4)
Private company staff	140 (27.9)	121 (48.4)	19 (7.6)
Voluntary organization staff	20 (3.9)	13 (5.2)	7 (2.8)
Sex work	227 (45.3)	30 (12.0)	197 (78.5)
Self-employed	39 (7.7)	29 (11.6)	10 (3.9)
Kadai Kettal (Asking alms from shops)	1 (0.2)	0 (0.0)	1 (0.4)
Current relationship status				<0.001
Currently single, no main partner	259 (51.7)	115 (46.0)	144 (57.4)
Partnered – with a boyfriend	178 (35.5)	89 (35.6)	89 (35.5)
Partnered – with a girlfriend	7 (1.4)	6 (2.4)	1 (0.4)
Married to a woman	33 (6.6)	33 (13.2)	0 (0.0)
Married to a man	9 (1.8)	4 (1.6)	5 (2.0)
Partnered - with a transgender woman	8 (1.6)	1 (0.4)	7 (2.8)
No answer/Not willing to answer	7 (1.4)	2 (0.8)	5 (2.0)
Self-reported sexual or sexual role-based identity among MSM
Kothi	72 (29.0)	72 (29.0)	-
Panthi	7 (2.8)	7 (2.8)	-
Double-Decker (Versatile)	21 (8.5)	21 (8.5)	-
Gay	82 (33.1)	82 (33.1)	-
Queer	6 (2.4)	6 (2.4)	-
Straight / Heterosexual	1 (0.4)	1 (0.4)	-
Bisexual	59 (23.8)	59 (23.8)	-
Self-reported gender-related identity among TGW
Thirunangai	242 (96.4)	-	242 (96.4)
Transgender woman (English term)	4 (1.6)	-	4 (1.6)
Woman	5 (2.0)	-	5 (2.0)
Education				<0.001
≤ Higher secondary	228 (45.5)	94 (37.6%)	134 (53.4)
≥ Diploma/college	273 (54.5)	156 (62.4%)	117 (46.6)
Recruitment mode				0.95
Offline	300 (59.9)	150 (60.0)	150 (59.8)
Online	201 (40.1)	100 (40.0)	101 (40.2)
HIV-positive status (Yes)	11 (2.2)	8 (3.2)	3 (1.2)	0.14
Outcomes
Awareness of mpox
Heard of mpox (Yes)	294 (58.7)	145 (58.0)	149 (59.4)	0.82
Awareness of burden of mpox among MSM/TGW (Yes)	186 (37.1)	89 (35.6)	97 (38.6)	0.54
Vaccine acceptability
Willingness to be vaccinated against mpox (Yes)	184 (36.7)	134 (53. 6)	50 (19.9)	<0.001
Psychosocial conditions
Depression (%)	208 (41.5)	44 (17.6)	164 (65.3)	<0.001
Anxiety (%)	276 (55.0)	79 (31.6)	197 (78.4)	<0.001
HIV/STI risk
Engaged in sex work in the past month (yes)	297 (59.3)	72 (28.8)	225 (89.6)	<0.001
Inconsistent condom use in the past 2 months (yes) with:
Any type of male partner	338/501 (67.4)	123/250 (49.2)	215/251 (85.6)	<0.001
Male non-regular partners	284/437 (64.9)	86/199 (43.2)	198/238 (83.1)	<0.001
Male regular partners	215/319 (67.4)	90/155 (58.0)	125/164 (76.2)	0.001

^ap-values were derived from independent samples t-tests for continuous variables and Pearson’s Chi-square or Fisher’s Exact tests for categorical variables. For the ‘occupation’ category, a p-value could not be computed due to small cell sizes.

Overall, 58.0% of MSM and 59.4% of TGW reported that they had heard about mpox before, and 35.6% of MSM and 38.6% of TGW reported that they knew that MSM and TGW are at an elevated risk of acquiring mpox. Overall, 53.6% of MSM and 19.9% of TGW were willing to take mpox vaccine.

More than half (54.5%) of the participants had a college or diploma degree; 29% of MSM and 90% of TGW reported engaging in the past month. Inconsistent condom use was high among both male regular partners (MSM: 42%; TGW: 24%) and non-regular partners (MSM: 57%; TGW: 17%). Eight (3.2%) MSM and three (1.2%) TGW were living with HIV. The prevalence of depression and anxiety was 17.6% and 31.6% among MSM and 65.3% and 78.4% among TGW.

Bivariate correlates of factors associated with mpox awareness and vaccination willingness

Several factors were significantly associated with mpox awareness (Table 2). Participants with prior PrEP awareness were more likely to be aware of mpox compared to those without (67.9% vs 51.9%). Additionally, older age (mean 29.7 vs 28.3 years), higher monthly income (mean INR 15,973 vs INR14,396), and completed COVID-19 vaccination schedule (60.5% vs 39.5%) were all associated with greater mpox awareness.

Table 2. Factors associated with mpox awareness and willingness for vaccination among study participants (n=501).

	Awareness of mpox			Willingness for mpox vaccination
Variable	No n (%)	Yes n (%)	P (χ2 or t-test)	No n (%)	Yes n (%)	P (χ2 or t- test)
Overall	207 (41.3)	294 (58.7)		317 (63.3)	184 (36.7)
Sociodemographics
Group			0.82			<0.0 01
MSM	105 (42.0)	145 (58.0)		116 (46.4)	134 (53.6)
TGW	102 (40.6)	149 (59.4)		201 (80.1)	50 (19.9)
Education			0.09			0.96
≤ higher secondary	104 (45.6)	124 (54.4)		145 (63.6)	83 (36.4)
≥ Diploma/ College degree	103 (37.7)	170 (62.3)		172 (63.0)	101 (37.0)
Recruitment mode			0.511			0.00 3
Offline	128 (42.7)	172 (57.3)		206 (68.7)	94 (31.3)
Online	79 (39.3)	122 (60.7)		111 (55.2)	90 (44.8)
HIV Status			0.21			0.02
HIV-negative	200 (40.8)	290 (59.2)		314 (64.1)	176 (35.9)
HIV-positive	7 (63.6)	4 (36.4)		3 (27.3)	8 (72.7)
Age (years) mean (SD)	28.3 (5.8)	29.7 (6.4)	0.01	28.8 (5.8)	29.6 (6.9)	0.19
Monthly income	14396	15973		15196	15575
(INR) mean (SD)	(7329)	(9811)	0.04	(7912)	(10480)	0.68
HIV/STI risk and prevention behaviors
Sex work (in the past month)			0.68			<0.0 01
No	87 (42.6)	117 (57.4)		99 (48.5)	105 (51.5)
Yes	120 (40.4)	177 (59.6)		218 (73.4)	79 (26.6)
Inconsistent condom use with any type of male partner (past 2 months)			0.31			<0.0 01
Always/Everytime	73 (44.8)	90 (55.2)		72 (44.2)	91 (55.8)
Never	134 (39.6)	204 (60.4)		245 (72.5)	93 (27.5)
Inconsistent condom use male non-regular partners (past 2 months)			0.51			<0.0 01
Always/Everytime	66 (43.1)	87 (56.9)		69 (45.1)	84 (54.9)
Never	112 (39.4)	172 (60.6)		213 (75.0)	71 (25.0)
Inconsistent condom use with male regular partner (past 2 months)			0.57			<0.0 01
Always/Everytime	36 (34.6)	68 (65.4)		45 (43.3)	59 (56.7)
Never	83 (38.6)	132 (61.4)		150 (69.8)	65 (30.2)
PrEP awareness			<0.00 1			0.21
No	139 (48.1)	150 (51.9)		190 (65.7)	99 (34.3)
Yes	68 (32.1)	144 (67.9)		127 (59.9)	85 (40.1)
Number of male non-regular sexual partners (past 2 months) mean (SD)	41.9 (3.9)	48.9 (3.4)	0.18	63.9 (3.5)	15.1 (1.9)	<0.0 01
Prior vaccination experience
COVID-19 vaccination (completed 2 doses)			0.01			0.66
No	26 (60.5)	17 (39.5)		29 (67.4)	14 (32.6)
Yes	181 (39.5)	277 (60.5)		288 (62.9)	170 (37.1)
Psychosocial conditions
Depression			0.316			<0.0 01
No	127 (43.3)	166 (56.7)		153 (52.2)	140 (47.8)
Yes	80 (38.5)	128 (61.5)		164 (78.8)	44 (21.2)
Anxiety
			0.08			<0.0 01
No	103 (45.8)	122 (54.2)		117 (52.0)	108 (48.0)
Yes	104 (37.7)	172 (62.3)		200 (72.5)	76 (27.5)
Ever heard of mpox?	-	-	-
(prior to survey)						0.07
No	-	-	-	141 (68.1%)	66 (31.9%)
Yes	-	-	-	176 (59.9%)	118 (40.1%)
Awareness of high burden of mpox among MSM/TGW	-	-	-			0.03
No	-	-	-	211 (67.0%)	104 (33.0%)
Yes	-	-	-	106 (57.0%)	80 (43.0%)

In relation to willingness for mpox vaccination (Table 2), MSM reported significantly higher willingness compared to TGW (53.6% vs 19.9%), and online-recruited participants showed greater willingness than offline-recruited participants (44.8% vs 31.3%). Lower vaccine willingness was associated with sex work engagement in the past month (26.6% vs 51.5%), inconsistent condom use, higher numbers of non-regular sexual partners (mean 63.9 vs 15.1), and presence of depression (21.2% vs 47.8%) or anxiety (27.5% vs 48.0%).

Multivariable predictors of awareness about mpox

In the model that included both MSM and TGW (Model 3.1, Table 3), a higher likelihood of awareness of mpox was predicted by older age (PRR=1.02, 95% CI 1.00 to 1.03, p=0.001), education of higher secondary or more (PRR=1.18, 95% CI 1.00 to 1.38, p=0.045), recruitment via online mode (PRR=1.28, 95% CI 1.06 to 1.56, p=0.012), prior awareness of PrEP (PRR=1.30, 95% CI 1.12 to 1.50, p<0.001), and a higher number of male non-regular sexual partners in the past two months (PRR=1.03 per 10-partner increment, 95% CI 1.01 to 1.05, p=0.012). For example, participants with prior awareness of PrEP had a 30% higher prevalence of mpox awareness compared to those without such awareness (PRR=1.30), with the confidence interval indicating the true prevalence ratio likely ranges from 12% to 50% higher prevalence.

Table 3. Multivariable predictors of awareness of mpox among men who have sex with men (MSM, n=250) and transgender women (TGW, n=251).

Predictors	Model 3.1. Awareness of Mpox among MSM & TGW (N=501)			Model 3.2. Awareness of Mpox among MSM			Model 3.3. Awareness of Mpox among TGW
	PRRa	95% CI	p	PRR	95% CI	p	PRR	95% CI	p
Sociodemographics
Age (years)	1.02	1.01 – 1.03	0.001	1.03	1.01 – 1.05	<0.001	1.01	0.99 – 1.03	0.19
Education: ≥ Higher secondary (Ref.: ≤ 10th grade)	1.18	1.00 – 1.38	0.045	1.46	1.12 – 1.89	0.005	0.99	0.80 – 1.21	0.89
Recruitment mode: Online (Ref.: Offline)	1.28	1.06 – 1.56	0.012	1.29	1.02 – 1.64	0.035	1.17	0.84 – 1.63	0.35
Subgroup: TGW (Ref.: MSM)	0.86	0.66 – 1.12	0.27	–	–		–	–	–
Recruitment mode: Online (Ref.: Offline)	1.28	1.06 – 1.56	0.012	1.29	1.02 – 1.64	0.035	1.17	0.84 – 1.63	0.35
HIV/STI risk
Sex work in the past month - Yes (Ref.: No)	1.01	0.81 – 1.25	0.92	1.03	0.78 – 1.35	0.83	1.20	0.75 – 1.93	0.44
ICCU with any male partner - Yes (Ref.: No)	1.05	0.88 – 1.26	0.56	1.08	0.87 – 1.33	0.47	1.03	0.70 – 1.51	0.89
Number of non-regular male sexual partners - in past 2 months (in increments of 10)	1.03	1.01 – 1.05	0.012	0.97	0.82 – 1.15	0.74	1.02	0.99 – 1.05	0.19
Other Infection Prevention Awareness PrEP awareness - Yes (Ref.: No)	1.30	1.12 – 1.50	<0.001	1.25	1.02 – 1.54	0.035	1.41	1.16 – 1.72	0.001

^aPrevalence Rate Ratio.

Note. Estimates are from a multivariable modified Poisson regression model with robust standard errors. Model 3.1 was adjusted for all variables listed in the table. Models 3.2 and 3.3 were adjusted for all variables listed, excluding ‘Subgroup’. ICCU: Inconsistent Condom Use with male partners; PrEP: HIV Pre-Exposure Prophylaxis.

In the model that included only MSM (Model 3.2, Table 3), significant predictors of mpox awareness included older age (PRR=1.03, 95% CI 1.01 to 1.05, p<0.001), education of higher secondary or more (PRR=1.64, 95% CI 1.12 to 1.89, p=0.005), recruitment via online mode (PRR=1.29, 95% CI 1.02 to 1.64, p=0.035), and prior awareness of PrEP (PRR=1.25, 95% CI 1.02 to 1.54, p=0.035).

In the model that included only TGW (Model 3.3, Table 3), prior awareness of PrEP was the only significant predictor of mpox awareness (PRR=1.41, 95% CI 1.16 to 1.72, p=0.001).

Multivariable predictors of mpox vaccination willingness

In the combined MSM and TGW sample (Model 4.1, Table 4), willingness to use the mpox vaccine was higher among those recruited online (PRR=1.52, 95% CI 1.19–1.93, p=0.001) and those aware of the higher mpox burden among MSM/TGW (PRR=1.31, 95% CI 1.01–1.69, p=0.041). The likelihood of willingness was lower among TGW compared to MSM (PRR=0.43, 95% CI 0.30–0.60, p<0.001), those reporting inconsistent condom use with any male partner (PRR=0.68, 95% CI 0.53–0.87, p=0.002), and those with depression (PRR=0.68, 95% CI 0.49–0.94, p=0.020).

Table 4. Multivariable predictors of willingness for mpox vaccination among men who have sex with men (MSM, n=250) and transgender women (TGW, n=251).

Predictors	Model 4.1. Mpox Vaccination Willingness among MSM & TGW			Model 4.2. Mpox Vaccination Willingness among MSM			Model 4.3. Mpox Vaccination Willingness among TGW
	PRRa	95% CI	p	PRR	95% CI	p	PRR	95% CI	p
Sociodemographics
Age (years)	1.01	0.99 – 1.03	0.35	1.00	0.98 – 1.02	0.85	1.00	0.97 – 1.03	0.92
Education: ≥ Higher secondary (Ref.: ≤ 10th grade)	0.80	0.63 – 1.02	0.07	0.94	0.74 – 1.21	0.66	0.65	0.42 – 1.03	0.06
Recruitment: Online (Ref.: Offline)	1.52	1.19 – 1.93	0.001	0.71	0.54 – 0.94	0.018	15.20	5.25 – 43.98	<0.001
Subgroup: TGW (Ref.: MSM)	0.43	0.30 – 0.60	<0.001	–	–	–		–	–
Awareness of mpox and PrEP
Prior awareness of Mpox – Yes (Ref.: No)	1.12	0.85 – 1.47	0.40	1.25	0.94 – 1.65	0.12	1.25	0.70 – 2.20	0.44
Awareness of burden of mpox among MSM/TGW – Yes (Ref.: No)	1.31	1.01 – 1.69	0.041	1.06	0.81 – 1.38	0.66	2.05	1.28 – 3.30	0.003
PrEP awareness - Yes (Ref.: No)	0.94	0.75 – 1.17	0.59	0.90	0.72 – 1.13	0.36	0.94	0.57 – 1.55	0.80
HIV/STI risk
Sex work in the past month - Yes (Ref.: No)	1.01	0.75 – 1.35	0.96	0.87	0.67 – 1.13	0.28	1.54	0.83 – 2.87	0.17
Inconsistent condom use with any male partner - Yes (Ref.: No)	0.68	0.53 – 0.87	0.002	0.84	0.66 – 1.07	0.16	0.68	0.41 – 1.12	0.13
Psychosocial problems
Anxiety - Yes (Ref.: No)	1.13	0.85 – 1.49	0.39	1.21	0.94 – 1.57	0.14	0.85	0.49 – 1.49	0.57
Depression - Yes (Ref.: No)	0.68	0.49 – 0.94	0.020	1.05	0.76 – 1.45	0.75	0.92	0.55 – 1.54	0.75
Health Protection Behavior
COVID vaccinated - Yes (Ref.: No)	0.73	0.50 – 1.07	0.11	0.70	0.44 – 1.12	0.13	0.82	0.49 – 1.38	0.46

^aPrevalence Rate Ratio

Note. Estimates are from multivariable modified Poisson regression models with robust standard errors. Model 4.1 was adjusted for all variables listed in the table. Models 4.2 and 4.3 were adjusted for all variables listed, excluding ‘Subgroup’. PrEP: Pre-Exposure Prophylaxis.

In the model that included only MSM (Model 4.2, Table 4), mpox vaccination willingness was lower among those recruited online (PRR=0.71, 95% CI 0.54–0.94, p=0.018).

In the model that included only TGW (Model 4.3, Table 4), willingness was higher among those aware of the mpox burden among MSM/TGW (PRR=2.05, 95% CI 1.28–3.38, p=0.003) and those recruited online (PRR=15.20, 95% CI 5.25–43.98, p<0.001.

Discussion

This study reveals suboptimal mpox awareness and low willingness for mpox vaccination among MSM and TGW in Chennai, India, underscoring a critical public health gap. Mpox vaccination willingness was particularly lower among TGW compared to MSM, individuals experiencing depression, and, concerningly, those engaging in inconsistent condom use – a group at heightened risk for sexually transmitted infections, including mpox. These findings signal an urgent need for tailored public health interventions to prevent future mpox outbreaks among vulnerable communities in India.

The suboptimal mpox awareness observed in our study (58.7%) among MSM and TGW in Chennai aligns with findings from other Asian countries where awareness has varied from 36.9%¹⁰ to 69.9%.¹¹ This likely reflects insufficient targeted public health campaigns on mpox for these vulnerable groups in India.²¹ In the present study, prior mpox awareness was positively associated with PrEP awareness, online recruitment, higher number of male non-regular sexual partners, older age, and higher educational level (observed in both combined and MSM-only models). These findings suggest that better access to information through online resources and HIV services provided by community-based organizations might have contributed to mpox awareness.^12,14 For instance, individuals with prior awareness of PrEP are likely more engaged with HIV and sexual health services, which may serve as mpox information channels.¹²

Our study’s finding of low overall mpox vaccine acceptability (36.7%) is concerning, particularly the very low rate among TGW (19.9%), when compared to the pooled willingness rate of 77% among MSM reported in a global meta-analysis.²⁸ In contrast to our study findings, studies conducted among MSM and TGW from other parts of the world have reported relatively higher mpox vaccination intentions (ranging from 66.2%¹⁴ to 91.4%¹¹) and actual mpox vaccination rates (ranging from 43.8% to 94.5%).¹³ The low acceptability in our sample could be attributed to limited educational interventions on mpox and its vaccine, coupled with the lack of readily available domestic mpox vaccines in India during the survey period and even in the first half of 2025.^6,29 The observation that awareness of higher mpox burden among MSM/TGW predicted greater vaccine willingness aligns with established health behavior theories and numerous studies where perceived susceptibility and severity positively influence vaccine uptake.^14,16,30

In the present study, several factors were associated with the willingness to be vaccinated. The lower willingness among TGW warrants further investigation, possibly linked to their lower prior mpox awareness, specific trust issues with the public health system, or other unmeasured socioeconomic vulnerabilities or beliefs (e.g., concerns about potential interactions between gender-affirming hormones and mpox vaccine), rather than solely educational attainment, which was not directly associated with their vaccine willingness. The negative association between depression and vaccine willingness observed in our study is consistent with other research indicating that mental health status can impact health-seeking behaviors, including vaccination.^31s,32s Intriguingly, we found that individuals reporting inconsistent condom use reported lower vaccination willingness, contrasting with findings where higher sexual risk behaviors often correlate with increased vaccine acceptance.^28,33s This may suggest a disconnect in perceiving mpox as a sexually transmissible infection or reduced risk perception among this subgroup.

The paradoxical finding of lower vaccine willingness among MSM recruited online, despite online recruitment being associated with higher mpox awareness among MSM, needs more exploration. Such exploration should particularly examine the role of mpox-related stigma, as mpox’s association with sexual transmission might discourage mpox vaccine uptake even when awareness is present.^34s Finally, the lack of association between prior COVID-19 vaccination and mpox vaccination intention in our study, unlike reports elsewhere,^33s,35s might be due to the near-universal and often mandated nature of COVID-19 vaccination in India, and its different perceived transmission routes compared to mpox.

Limitations

Our study has several limitations. First, the recruitment strategies, relying on community-based organizations for offline surveys and self-administered online surveys for eligible, self-selected participants, may introduce self-selection bias, potentially limiting the generalizability of our findings. However, recognizing that MSM and TGW face systemic barriers to research participation, we employed diverse outreach methods to increase the diversity of the survey participants. Second, as the survey’s primary focus was not mpox but rather stigma and sexual risk within a larger study, mpox awareness was assessed using a single question, precluding a comprehensive knowledge assessment. Therefore, caution is warranted in interpreting the prevalence of mpox awareness and its predictors; nevertheless, the significant predictors identified for both mpox awareness and vaccination willingness were largely consistent with findings from other international studies. Third, social desirability bias could have led to underreporting or misreporting on sensitive questions like condom use and the number of sexual partners. To mitigate this, we engaged trained community interviewers, which likely fostered greater trust with participants, thereby potentially reducing such bias. The observation that condom use and partner numbers still emerged as significant predictors, despite their sensitivity, lends some support to the notion that this bias may have been at least partially managed in this sample.

Implications for Policy, Programs, and Practice

Our findings of suboptimal mpox awareness and vaccination willingness, particularly low among TGW, those with depression, and individuals reporting inconsistent condom use, necessitate immediate public health action. Programmatically, interventions must extend beyond simple information dissemination to address psychosocial determinants of vaccine hesitancy, such as depression,^36s and specifically tailor messages towards individuals reporting inconsistent condom use and that can overcome literacy concerns. To ensure cultural sensitivity and avoid exacerbating stigma, it is imperative that all health communication is co-designed with MSM and TGW community members, in collaboration with community-based organizations. From a policy perspective, given our findings of low vaccine acceptability, particularly among economically disadvantaged populations, enhancing domestic mpox vaccine production capabilities would be crucial for national outbreak preparedness by reducing costs and leveraging the demonstrated trust in India-made vaccines that contributed to successful COVID-19 vaccination campaigns.^6,29 Furthermore, developing clear national guidelines for equitable access for at-risk populations like MSM and TGW, would be a prudent step for contingency planning. Clinically, ongoing vigilance and readiness are important. Healthcare providers, especially within STI/HIV services, would benefit from training to recognize diverse presentations of mpox and to create non-discriminatory environments that encourage disclosure of same-sex sexual behaviors among MSM.^37s,38s Such trainings should include skills for sensitively taking sexual histories and building trust with marginalized communities, as MSM are more likely to disclose their sexual behaviors when they feel safe from discrimination. This enhanced capacity to identify at-risk individuals through improved patient-provider communication would enable healthcare providers to proactively counsel MSM and TGW clients on mpox prevention strategies and vaccination benefits during routine visits, rather than waiting for symptomatic presentations. Effectively addressing these multifaceted aspects through targeted, evidence-informed, and non-stigmatizing approaches is essential for protecting these vulnerable communities, should mpox become a more significant public health concern in the future.

Conclusions

This study highlights the critical need to address suboptimal mpox awareness and notably low mpox vaccine acceptability among MSM and TGW. Lower mpox vaccine willingness was particularly evident among TGW, individuals experiencing depression, and those reporting inconsistent condom use, placing them at elevated risk for future mpox outbreaks. To reduce stigma and enhance impact, mpox education and vaccination initiatives should be integrated into existing HIV and sexual health services and co-designed with community members. Enhancing equitable access for vulnerable communities, including MSM and TGW, alongside maintaining clinical vigilance, will be pivotal for effective outbreak preparedness in India.

Summary.

Among MSM and transgender women in India, mpox awareness and vaccine acceptability were low, particularly among transgender women, those with depression, and those who reported inconsistent condom use.