25 Years after Vi Typhoid Vaccine Efficacy Study, Typhoid Affects Significant Number of Population in Nepal

Abstract

Salmonella Typhi, first isolated in 1884, results in infection of the intestines and can end in death and disability. Due to serious adverse events post vaccination, whole cell killed vaccines have been replaced with new generation vaccines. The efficacy of Vi polysaccharide (ViPS) vaccine, a new generation, single-dose intramuscular typhoid vaccine was assessed in Nepal in 1987. However, despite the availability of ViPS vaccine for more than 25 years, Nepal has one of the highest incidence of typhoid fever. Therefore we collected information from hospitals in the Kathmandu Valley from over the past five years. There were 9901 enteric fever cases between January 2008 and July 2012. 1,881 of these were confirmed typhoid cases from five hospitals in the Kathmandu district. Approximately 70% of the cases involved children under 15 years old. 1281 cases were confirmed as S. Paratyphi. Vaccines should be prioritized for control of typhoid in conjunction with improved water and sanitation conditions in Nepal and in endemic countries of Asia and Africa.

Factors Associated Participation in a School Based Typhoid Vaccination Campaign in Nepal

“…Children in this age group have high rates of typhoid fever. In addition, resistance to commonly used antibiotics continues to increase in south Asia and in Nepal [13]. The Vi vaccine pilot introduction project was developed with support from the IVI and implemented by the District Public Health Office of Lalitpur District, Kathmandu Valley, Nepal with a help of a non-governmental organization, MITRA Samaj between 2010 and 2013.…”

Incubation period of typhoidal salmonellosis: a systematic review and meta-analysis of outbreaks and experimental studies occurring over the last century

“…It is recommended to people living in or visiting endemic areas and to control outbreaks [ 3 ]. Our study did not aim to review the efficacy of typhoid vaccine in preventing outbreaks, however we identified a couple of studies with outbreaks reported in vaccinated population [ 28 , 29 ] and similar studies have also been reported [ 30 ]. As observed from our review, we may say that in populations where vaccination does not prevent illness, it may delay the onset of symptoms thereby prolonging the incubation period.…”

Serological Diagnosis of Salmonella typhi in DHQ (District Head Quarter Hospital) of Charsadda, City of Kp Pakistan 2015-2016

“…Numerous cases have been accounted for all through the entire year. Like other Asian countries; typhoid fever can be a critical pointer of the financial state of the populace [12]. Sarwari & Sulaiman in 2007 reported about the worldwide the most notorious hotspots for typhoid fever are Pakistan, India, Nepal, Peru, Indonesia, Egypt and Mexico [13].…”