Correspondence www.thelancet.com Published online June 16, 2015 http://dx.doi.org/10.1016/S0140-6736(15)61110-2 1 the basis of identification of high-risk populations and the available organisational capacity for safe implementation and monitoring of outcomes. HRD received travel, accommodation costs, and consultancy fees from GlaxoSmithKline, Wantai, and Roche; travel, accommodation, and lecture fees from Merck, Gilead, and GFE Blut GmBh; travel and accommodation fees from the Gates Foundation. NK received travel, accommodation costs, and consultancy fees from Novartis and Merck; travel, accommodation, and lecture fees from Gilead, Novartis, Astellas, BMS, Amgen, and Fresenius; travel and accommodation fees from the Gates Foundation. PP received support from Gates Foundation, IMI, and UNAIDS, and is a board member of Biocartis. The other authors declare no conflicts of interest. Buddha Basnyat, *Harry R Dalton, Nassim Kamar, David B Rein, Alain Labrique, Jeremy Farrar, Peter Piot, on behalf of 21 signatories harry.dalton@rcht.cornwall.nhs.uk Oxford University Clinical Research Unit-Patan Academy of Health Sciences, Kathmandu, Nepal (BB); Royal Cornwall Hospital and University of Exeter, Truro, UK (HRD); Department of Organ Transplantation, CHU Rangueil, INSERM U1043, IFR–BMT, Université Paul Sabatier, Toulouse, France (NK); Public Health, NORC, University of Chicago, Chicago, USA (DBR); Epidemiology, Environmental Health Sciences, and International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, USA (AL); Wellcome Trust, London, UK (JF); and London School of Hygiene & Tropical Medicine, London, UK (PP) 1 International Society for Infectious Diseases. Diarrhea, post-earthquake—Nepal (Central region). http://promedmail.org/direct. php?id=20150429.3330811 (accessed June 9, 2015). 2 International Society for Infectious Diseases. Hepatitis—Nepal (Kathmandu) Earthquake- related. http://www.promedmail.org/direct. php?id=3338560 (accessed June 9, 2015). 3 Kamar N, Bendall R, Legrand-Abravanel F, et al. Hepatitis E. Lancet 2012; 379: 2477–88. Nepali earthquakes and the risk of an epidemic of hepatitis E The recent earthquakes in Nepal killed thousands, displaced tens of thousands, and destroyed much of the country’s infrastructure. Thousands of Nepalis are living in makeshift camps, with limited or no access to clean drinking water. There is now considerable risk of infectious diseases in affected areas. 1,2 Of particular concern is the risk of an epidemic of hepatitis E. Sporadic cases of hepatitis E are common in Nepal. Most have a self-limiting illness, but pregnant women have a mortality of 25%. 3 There have been a number of large outbreaks of hepatitis E in Nepal, including one in 2014, which involved more than 10 000 cases. 4 Earthquake- affected areas are faced with a “perfect storm” of risk factors: large displaced populations with limited access to clean drinking water, lack of sanitary facilities, the approaching monsoon, overburdened health- care infrastructure, large amounts of circulating hepatitis E virus (HEV), and an at-risk population who mostly lack protective antibodies (approximately 70% of the at-risk population lack protective anti-HEV IgG antibodies [Basnyat B, unpublished]). As a group of HEV and infectious disease international experts (see appendix), we estimate the risk of an outbreak of hepatitis E as very high, imminent (likely onset: monsoon season, July–September), with possibly more than 500 deaths among pregnant women (table). A safe and effective vaccine (HEV239) is available, but is currently only licensed for use in China. 7 HEV239 has not yet received WHO vaccine prequalification, and WHO’s Strategic Advisory Group of Experts on Immunization did not recommend its routine use in highly endemic areas because of the need for additional safety and efficacy data, particularly in pregnant women. However, their recently released hepatitis E position paper states that current WHO position should not preclude the use of the vaccine in specific situations. “In particular, the use of the vaccine to mitigate or prevent outbreaks of hepatitis E should be considered as well as the use of the vaccine to mitigate consequences in high risk groups such as pregnant women.” Its use in Nepal, if an outbreak occurs, might prevent the deaths of more than 400 pregnant women, according to our estimates (table). To minimise risk to human health, we recommend: first, deploy an active surveillance mechanism to identify cases of hepatitis E using point-of- care testing; second, the Ministry of Health of Nepal should initiate a request for HEV239 vaccine, and pre-emptively build a local reserve of vaccine doses; third, development of targeted deployment strategies and guidelines for the use of HEV239 on See appendix for signatories Published Online June 16, 2015 http://dx.doi.org/10.1016/ S0140-6736(15)61110-2 Pregnant women Without vaccination With vaccination Effect of vaccination Total Symptomatic cases Deaths Symptomatic cases Deaths Symptomatic cases Deaths Very severely affected zone 16 400 701 173 98 24 –603 –149 Severely affected zone 3263 140 34 20 5 –120 –30 Moderately affected zone 13 056 558 138 78 19 –480 –119 Slightly affected zone 15 549 665 164 93 23 –572 –141 Total 48 268 2064 510 289 71 –1775 –438 Data were modelled using past estimates of the incidence, anti-HEV IgG seroprevalence data from the population of the Kathmandu valley (2010–12) and impacts of hepatitis E during outbreaks in refugee conditions (data were from Basnyat B [unpublished] and reference 5). The modelling was done after the first earthquake (April 25) and before the second one (May 12). Earthquake affected zones are classifed by severity as shown in reference 6. Table: Estimation of the number of deaths among pregnant women with and without hepatitis E vaccination, and potential effect of vaccination, by earthquake affected zone For the WHO hepatitis E position paper see http://www. who.int/immunization/policy/ position_papers/hepatitis_e/en/ For more on the modelling see http://www.norc.org/PDFs/ Hep%20E%20Model%20 Documentation.pdf See Online for appendix