Seroprevalence Survey of Chikungunya Virus in Bagan Panchor, Malaysia

Abstract

In 2006, an outbreak of Chikungunya virus (CHIKV) of the Asian genotype affected over 200 people in Bagan Panchor village in Malaysia. One year later, a post-outbreak survey was performed to determine attack rate, asymptomatic rate, and post-infection sequelae. Findings were compared with recent CHIKV outbreaks of the Central/East African genotype. A total of 180 residents were interviewed for acute symptoms and post-infection physical quality of life and depressive symptoms. Sera from 72 residents were tested for CHIKV neutralizing antibodies. The estimated attack rate was 55.6%, and 17.5% of infected residents were asymptomatic. Arthralgia was reported up to 3 months after infection, but there were no reports of long-term functional dependence or depression. Symptomatic and seropositive residents were significantly more likely to live in the area with the most dense housing and commercial activities. CHIKV had a high attack rate and considerable clinical impact during the Bagan Panchor outbreak.

Chikungunya virus outbreak in Kerala, India, 2007: a seroprevalence study

“…Studies also showed that seroprevalence was greater in the part of the village with more human activity. Besides, differences in attack rates were likely caused by local factors, including population immunity and genetic susceptibility, vector competence, environmental settings and effectiveness of outbreak control measures (Ayu et al 2010). In Mayotte, CHIKV seroprevalence was higher in households with structural risk factors for mosquito breeding or exposure, such as open yards (Raude & Setbon 2009).…”

Chikungunya virus: epidemiology, replication, disease mechanisms, and prospective intervention strategies

“…In humans, IFN-α appears early in infection and correlates with viral load (111,114,117). Coincident with rising viral loads and IFN-α responses, the vast majority of infected patients experience sudden onset of clinical illness (Table 1), with a small proportion of infected individuals (5%-28%) remaining asymptomatic (118,119). Acute CHIKV infection is predominated by high fever (39°C-40°C), which can last up N-terminus of E3 traffics the major and minor structural polyproteins through the host secretory pathway, where cleavage by host proteases produces pE2 (E3-E2); 6K or transframe (TF); and E1.…”

Epidemiology of Chikungunya in the Americas

“…Studies of prior outbreaks have determined that 10%–70% of persons in an affected area become infected [1, 2]. This potentially high infection rate is coupled with a high symptomatic attack rate among infected people, with 50%–97% developing clinical disease with fever and polyarthralgia [2–4], and yields large outbreaks of disease that often tax existing healthcare systems and public health infrastructure.…”

“…These findings suggest that the CHIKV was broadly transmitted during the outbreak. A total of 3%–22% of infected patients are asymptomatic or pauci-symptomatic [2, 4]. …”