Kyasanur Forest Disease, India, 2011–2012 - Vol. 19 No. 2 - February 2013 - Emerging Infectious Disease journal - CDC

full-text ►
Kyasanur Forest Disease, India, 2011–2012 - Vol. 19 No. 2 - February 2013 - Emerging Infectious Disease journal - CDC

Georges de La Tour (1593‒1652) La Femme à la puce (The Flea Catcher) (1638) Oil on canvas (90 cm × 120 cm) Musée Lorrain, Nancy. Photo P. Mignot

Volume 19, Number 2—February 2013

Dispatch

Kyasanur Forest Disease, India, 2011–2012

Article Contents

• The Study


• Conclusions


• Acknowledgments


• References


• Figure 1


• Figure 2


• Table 1


• Table 2


• Technical Appendix  [75 KB - 1 page]


• Suggested Citation

Gudadappa S. Kasabi, Manoj V. Murhekar , Pragya D. Yadav, R. Raghunandan, S.K. Kiran, V.K. Sandhya, G.H. Channabasappa, Akhilesh C. Mishra, Devendra Tarachand Mourya, and Sanjay M. Mehendale

Author affiliations: Author affiliations: National Institute of Epidemiology, Chennai, India (G.S. Kasabi, M.V. Murhekar, S.M. Mehendale); National Institute of Virology, Pune, India (P.D. Yadav, A.C. Mishra, D.T. Mourya); Department of Health and Family Welfare of the Government of Karnataka in Shimoga District, Shimoga, India (G.S. Kasabi, R. Raghunandan, S.K. Kiran, G.H. Channabasappa); Virus Diagnostic Laboratory, Shimoga, India (V.K. Sandhya)

Suggested citation for this article

Abstract

To determine the cause of the recent upsurge in Kyasanur Forest disease, we investigated the outbreak that occurred during December 2011–March 2012 in India. Male patients >14 years of age were most commonly affected. Although vaccination is the key strategy for preventing disease, vaccine for boosters was unavailable during 2011, which might be a reason for the increased cases.

Kyasanur Forest disease (KFD), a tick-borne viral disease, was first recognized in 1957 in Shimoga District, India, when an outbreak in monkeys in Kyasanur Forest was followed by an outbreak of hemorrhagic febrile illness in humans (1). KFD is unique to 5 districts (Shimoga, Chikkamagalore, Uttara Kannada, Dakshina Kannada, and Udupi) of Karnataka State and occurs as seasonal outbreaks during January–June (2–4).
Since 1990, vaccination campaigns using formalin-inactivated tissue-culture vaccine have been conducted in the districts to which KFD is endemic (Directorate of Health and Family Welfare Services, Government of Karnataka, Manual on Kyasanur Forest disease. 2005, unpub. data). Earlier studies showed vaccine efficacy of 79.3% with 1 dose and 93.5% with 2 doses (5,6). The vaccination program identifies villages reporting KFD activity (laboratory-confirmed cases in monkeys and/or humans, or infected ticks), and all villages within 5 km of the affected location are targeted for vaccination. Two doses are administered to persons 7–65 years of age at 1-month intervals. Because the immunity conferred by vaccination is short-lived, booster doses are administered at 6–9-month intervals consecutively for 5 years after the last reported KFD activity in the area (Directorate of Health and Family Welfare Services, Government of Karnataka, Manual on Kyasanur Forest disease. 2005, unpub. data). If KFD activity is reported where vaccination has been administered during pretransmission seasons, additional vaccination campaigns are conducted.

Figure 1

Figure 1. . . Location of Thirthahalli Taluka, Shimoga District, Karnataka State, India.

Thirthahalli Taluka in the Shimoga District (Figure 1), where vaccination campaigns were ongoing, reported 0 cases of KFD during 2007–2010. A vaccination campaign was conducted in the area during October 2010. Because 11 cases were reported from the Thirthahalli Taluka in March 2011, vaccination campaigns were conducted during April–May 2011; however, no booster doses were administered in the affected areas during October–November 2011 because the vaccine was not available. Suspected KFD cases were reported in the area again in December 2011. We investigated this cluster to 1) confirm the etiology, 2) identify risk factors, and 3) propose recommendations for control.