Table 2.
Case examples of herd and rebound effects per type of disease and per region
| Disease | Region | Country | Author / Year / Reference | Vaccine | Vaccination parameters | Type of study | Difference in outcomes* due to herd protection (HP) and/or rebound effects |
|---|---|---|---|---|---|---|---|
| ROTAVIRUS | Europe | France, Germany, Italy, Spain, UK | Van Effelterre 200924 | Rotarix™ | Infants ≤ 5 yrs 70, 90, 95% coverage5-yr time horizon | Dynamic model | Incidence of any RVGE due to HP:25%, 22%, & 20% ↓ for coverage rates of 70%, 90%, 95%Incidence of severe RVGE due to HP:19%, 15%, & 13% ↓ for coverage rates of 70%, 90%, 95% |
| UK | Atkins 2012130 | Rotarix™ & RotaTeq™ | Infants <5 yrs 95% coverage 1-yr time horizon | Dynamic model | Incidence due to HP:29% ↓ any dz. 18% ↓ severe dz. | ||
| Netherlands | Tu 2013131 & Rozenbaum 2011132 | Rotarix™ & RotaTeq™ | Infants <5 yrs 95% coverage 5-yr time horizon | Static model | Hospitalisations due to HP (original study):No HP = 353 casesHP = 155 cases ICER in €/QALY (updated hospitalization results):No HP = € 15,600HP = € 3,800 | ||
| Belgium | Raes 201131 | Rotarix™ & RotaTeq™ | Infants ≤5 yrs (only ages 2–24 months vacc.)90 coverage 2 yrs pre- & post-vacc. | Observational | Hospitalisations due to HP:50% & 64% ↓ in the <2 month-olds (yr 1 & 2 post-vacc.) 20% & 64% ↓ in the >24 months-olds (yr 1 & 2 post-vacc.) | ||
| Belgium | Standaert 2013133 | Rotarix™ & RotaTeq™ | Infants ≤5 yrs (vacc. infants compared with unvacc. <3 months)60–85% coverage5-yr time horizon | Observational data compared with cohort model predictions | Hospitalisations due to HP:(# of cases pre-vacc., 2nd, 3rd, and 4th yr post-vacc., respectively) 0–1 months: 18, 12, 4 & 6 cases1–2 months: 46, 8, 13, 11 cases2–3 months: 38, 23, 14, 6 casesOverall improvement of the hospitalisation results by 10% across all age groups due to HP | ||
| North America | USA | Shim 2009134; Aballea135 | RotaTeq™ | Infants <5 yrsCoverage (% unknown)20-yr time horizon | Dynamic model | Incidence due to HP:41% ↓ in mild cases 24% ↓ Hospitalisations cases | |
| USA | Lopman 2011136 | Roatrix™ & RotaTeq™ | Infants ≤5 yrs | Observational | Hospitalisations due to HP:5–14 yr. olds No HP = 1801HP = 747 (RR 0.29)14–24 yr. olds No HP = 127HP = 70 (RR 0.35) | ||
| USA | Payne 201143 | Rotarix™ & RotaTeq™ | Infants <3 yrs Coverage:6–11 months = 77% 12–23 months = 46% 24–35 months = 1% 1-yr timeframe | Observational | Hospitalisations due to HP: 87% ↓ among the 6–11 month-olds 96% ↓ among the 12–23 month-olds 92% ↓ among the 24–35 month-olds | ||
| HPV | Europe | Netherlands | Bogaards 201168 | 12-yr old girls50 & 70% coverageLifetime risk | Dynamic model | Incidence of cervical cancer due to HP: ↓ of 68 cases/100,000 women (50% coverage of girls) ↓ of 64 cases/100,000 women (70% coverage of girls)20–27% of total number of cases averted due to HP | |
| 26 EU countries | Marty 2013137 | Quadrivalent | 12-yr old girls70% coverageLifetime risk | Dynamic model | Incidence of HPV 16/18-related carcinomas due to HP:61% ↓ in boys | ||
| Denmark | Sando 2014138 | Quadrivalent | 12–16 yr old girls 80–90% coverage4-yr timeframe | Observational | Incidence of anogenital warts due to HP: 50% ↓ among 15–19 yr-old men ↓ from 5.2 to 2.6/1,000 men | ||
| North America | Canada | Van de Velde & Brisson 2010 and 2011139, 140 | Quadrivalent | 12-yr old girls70% coverage20–30-yr time horizon | Dynamic model | Incidence of HPV 16/18 due to HP: 86% ↓in males (30-yr timeframe) 62–65% ↓ in males (20-yr timeframe) | |
| USA | Elbasha 2007 | Quadrivalent | <12-yr old girls70% coverage Lifelong risk | Dynamic model | Incidence of genital warts due to HP: ↓from 160/100,000 to 60/100,000 in males ≥12 yrs old (approximately 63% ) | ||
| USA | Kahn 2012142 | Quadrivalent | 11–12 yr old girlsCoverage (% unknown) 2 point prev. tests | Observational (surveillance study) | Incidence of HPV vaccine-related types due to HP: ↓ 15–30% in unvaccinated females 13–26 yrs old | ||
| HEPATITIS A | Europe | Spain | Dominguez 200841 | HAV | Children ≤12 yrs91% coverage6-yr overall post-vacc. | Observational | Incidence of hepatitis A due to HP: ↓ 49% among unvaccinated 20–29 yr-olds ↓ from 9.96 to 5.08 per 100,000 |
| North America | USA | Samandari 200427 | HAV | Children 2–18 yrs old10% coverage1-yr time horizon | Dynamic model | Incidence of hepatitis A due to HP: ↓ 32% among unvaccinated adults >18 yrs old ↓ 51% in the vaccinated cohort (despite only 10% coverage) | |
| USA | Armstrong 200647 | HAV | Infants 1 yr oldCoverage (% unknown)10-yr time horizon | Dynamic model | Incidence of hepatitis A due to HP:Savings of $19.8 million 3,684 QALY's and 675 LY's saved ↓ from $32,000 to $1,000 per QALY gained | ||
| USA | Wasley 200546 | HAV | Children (age not given) Coverage (% unknown)1-yr post-vacc. | Observational | Incidence of hepatitis A due to HP:53% in non-vacc. States (=33) compared to vacc. States (=17) Relative proportion of adults while actual rates, except among adults ≥55 yrs in non-vacc. States | ||
| Canada | Bauch 2007143 | HAV | Infants 1 yr old Coverage (% unknown)80-yr time horizon | Dynamic model | Incidence (annual) of hepatitis A (per 100,000) due to HP: 5–9 yr-olds: ↓ from 21.2 to 1.9 10–19-yr olds: ↓ from 13.0 to 1.720–29-yr olds: ↓ from 13.1 to 2.230–39-yr olds: ↓ from 14.0 to 1.940–59-yr olds: ↓ from 9.5 to 1.460+: ↓ from 9.4 to 1.5 | ||
| Asia | Israel | Dagan 200551 | HAV | Toddlers 18–24 months85–90% coverage3-yr timeframe | Observational | Incidence of hepatitis A due to HP: ↓ 77–95% among all unvaccinated age groups (<1 yr old & 5 to >65 yrs old) | |
| PERTUSSIS | Europe | Sweden | Taranger 2001144 | Pertussis only | Infants89% coverage 3-yr timeframe | ObservationalProspective | Incidence of pertussis due to HP: ↓ 96% among adults ≥15 yrs old |
| Sweden | Trollfors 199829 | DTPtxd | Infants2-yr time horizon | Randomized clinical trial (compared to non-vacc.) | Incidence of pertussis due to HP: ↓ 44% protection in parents of pertussis cases43–56% protection of younger siblings | ||
| North America | USA | Lee 2007145 | Tdap & DTaP | Adults 20–64 yrs(1x & decennial booster)57–66% coverageLifetime horizon | Cohort model(Sensitivity Analysis only) | Incidence of pertussis due to HP: ↓ 15% among infants (1x adult booster)0%, 15%, 30, & 45% (decennial boosters) | |
| Caro 2005125 | Tdap & DTaP | Adolescents 11–18 yrs 80% coverage Lifetime horizon | Cohort model(assumed rate of HP only) | Incidence & costs of pertussis due to HP: ↓ 68,408 casesSavings of $18.3 million5% HP: ↓ $187,081 / LYG20% HP: ↓ $ 6,253 / LYG | |||
| Guris 200860 | Tdap & DTaP | Preschool aged children85% coverage 2-yr timeframe | Observational | Incidence of pertussis due partly to age shift post-vaccination (other factors also possible):40% ↓ among 5–9 yr-olds 106% ↓among 10–19 yr-olds 93% ↓among ≥20 yr-olds | |||
| VARICELLA** | Europe | Germany | Streng 201349 | Varicella | Infants 18–36 monthsIncreasing coverage (up to 68% in 2011)5-yr timeframe | Observational(varicella only) | Incidence of varicella due to HP: 71% ↓among older children 63% ↓ among adolescents |
| UK | Brisson 2006103 | Varicella | Infants 1 yr old90% coverage80-yr time horizon | Dynamic model(herpes zoster) | Deemed cost-effectiveness due to the rebound effect of varicella vacc. on herpes zoster:0% of modelled simulations incl. zoster are CE (<≤30,000) compared to nearly 100% of simulations for a varicella-only effect | ||
| Finland, Italy, UK | Poletti 201387 | Varicella | Infants 1 yr old100% coverage100-yr time horizon | Dynamic model(herpes zoster) | Incidence of herpes zoster due to the rebound effect of varicella vacc.17–32% average for 40–60 yrs post-vacc., or an ↓ from 2.69 to 3.54 per 1000 persons/yr, followed by a gradual decline in incidence (Italy)No/minimal increase seen in Italy & the UK | ||
| North America | USA | Zhou 200595 | Varicella | Infants 12–18 monthsIncreasing coverage (up to 81% in 2002)9-yr timeframe | Observational(varicella only) | Hospitalisations of varicella due to HP: ↓ 78% ↓ among adults 20–49 yrs old | |
| USA (CA & PA States) | Marin 200889 | Varicella | InfantsHigh coverage (% unknown)11-yr timeframe (1995–2005) | Observational(varicella only) | Incidence of varicella due to HP: ↓ 74% ↓ among adults ≥20 yrs old | ||
| USA | Leung 2011111 | Varicella | Infants 19–35 months68% (2000) to 89% coverage (2006)14-yr timeframe (1993–2006) | Observational(herpes zoster) | Incidence of herpes zoster due to the rebound effect of varicella vacc.98% average ↓ (standardized by age and gender) |
*
Differences in outcomes due to vaccination (effect difference).
**
Varicella and herpes zoster are related, but most of the studies evaluated varicella only.
↓
: decrease or reduction, ↑: increase, CA: California, PA: Pennsylvania, DTPtxd: diphtheria, tetanus and pertussis toxoids Tdap & DTaP: tetanus-diphtheria-acelluar pertussis & Diphtheria, tetanus, and pertussis vaccine, Dz: disease, HAV: Hepatitis A virus, HP: herd protection, HPV: Human papillomavirus, ICER: incremental cost-effectiveness ratio, QALY's = Quality Adjusted Life Years, RR: Relative rate, RVGE: rotavirus gastroenteritis, Vacc: vaccination or vaccinating Yr(s): year(s).