Leptospirosis following heavy rains in 2017 in Mumbai: Report of large-scale community chemoprophylaxis.

Background: Globally, cities get flooded due to heavy rains. As the incidence of leptospirosis increases after such flooding in Mumbai, community chemoprophylaxis to selected individuals was a consensus recommendation by experts.

Methods: We surveyed a total of 1 499 293 houses in severely affected areas of Mumbai (where there was waterlogging or high incidence of leptospirosis in the past) as well as in all slum areas. A total of 6 714 210 people (>50% of the population) were screened. A total of 156 934 adults, 4465 children, 359 pregnant women and 4957 high-risk adults were given prophylaxis with doxycycline or azithromycin by paramedical staff (n = 9526) under the supervision of medical staff. Social media and newspaper advertisements were used to create public awareness.

Results: Compared with previous floods, there were reduced number of cases of leptospirosis due to community chemoprophylaxis (432 confirmed cases in 2005 v. 128 [59 confirmed] in 2017).

Conclusions: Selective, time-bound chemoprophylaxis following floods is likely to reduce the incidence of leptospirosis, as well as associated morbidity and mortality.