Table II.
Age- and sex-stratified infection fatality ratios, August and October 2020, Chennai, India
| Characteristics | First serosurvey (July17-28, 2020) | Second survey (October 8-15, 2020) | ||||
|---|---|---|---|---|---|---|
|
|
|
|||||
| Number of COVID-19 deaths* | Number of COVID-19 infections (95% CI) | IFR per 10,000 infections (95% CI) | Number of COVID-19 deaths** | Number of COVID-19 infections (95% CI) | IFR per 10,000 infections (95% CI) | |
| Overall | 2246 | 1,295,908 (1,040,975-1,593,330) | 17.3 (14.1-21.6) | 3520 | 2,473,238 (2,029,534-2,966,242) | 16.6 (13.8-20.2) |
| Sex | ||||||
| Male | 1556 | 574,859 (454,209-716,799) | 27.1 (21.7-34.3) | 2438 | 1,222,608 (999,565-1,474,564) | 23.3 (19.3-28.5) |
| Female | 690 | 713,657 (57,5872-879,706) | 9.7 (7.8-12.0) | 1082 | 1,250,409 (1.021,576-1,503,760) | 10.0 (8.4-12.3) |
| Age (yr) | ||||||
| 10-19 | 5 | 234,050 (180,914-298,571) | 0.2 (0.2-0.3) | 5 | 320,058 (248,234-401,963) | 0.2 (0.1-0.2) |
| 20-29 | 26 | 333,664 (264,352-415,871) | 0.8 (0.6-1.0) | 33 | 463,976 (372,465-568,331) | 0.7 (0.6-0.9) |
| 30-39 | 82 | 264,175 (207,253-331,313) | 3.1 (2.5-4.0) | 104 | 465,181 (376,506-565,486) | 2.2 (1.8-2.8) |
| 40-49 | 209 | 220,481 (173,399-276,749) | 9.5 (7.6-12.1) | 292 | 383,154 (311,098-463,216) | 7.6 (6.3-9.4) |
| 50-59 | 447 | 156,962 (123,215-196,987) | 28.5 (22.7-36.3) | 640 | 240,755 (191,509-297,035) | 26.6 (21.5-33.4) |
| ≥60 | 1477 | 105,528 (80,364-137,998) | 140.0 (107.0-183.8) | 2446 | 219,914 (172,212-274,084) | 111.2 (89.2-142.0) |
*Deaths as on August 3, 2020, **Deaths as on October 23, 2020. CI, confidence interval; IFR, infection fatality ratio