|Year : 2016 | Volume
| Issue : 2 | Page : 213-215
Chikungunya virus infection in West Bengal, India
S Chattopadhyay1, R Mukherjee2, A Nandi3, N Bhattacharya4
1 Department of Microbiology, Burdwan Medical College, Burdwan, India
2 Department of Pathology, Sub-divisional Hospital, Chandannagore, Hooghly, India
3 Department of Microbiology, Medical College, Virology Unit, School of Tropical Medicine, Kolkata, West Bengal, India
4 Department of Microbiology, Virology Unit, School of Tropical Medicine, Kolkata, West Bengal, India
|Date of Submission||13-Jun-2015|
|Date of Acceptance||23-Sep-2016|
|Date of Web Publication||14-Apr-2016|
Department of Microbiology, Burdwan Medical College, Burdwan
Source of Support: None, Conflict of Interest: None
Background: Chikungunya virus has recently re-emerged in India. Objectives: Assess prevalence of Chikungunya. Materials and Methods: Study conducted from April 2011 to September 2011. Two hundred and six patients (206) of both sexes (100 males and 106 females) of all age groups studied. Serum separated and CHIKV MAC IgM ELISA and Hemagglutination inhibition assay done. Results: 76 cases (36.89%) sero-positive by both the methods. Conclusion: Re-emergence and resurgence of the Chikungunya virus requires continuous monitoring.
Keywords: Chikungunya, Chikungunya virus MAC IgM ELISA, hemagglutination inhibition assay
|How to cite this article:|
Chattopadhyay S, Mukherjee R, Nandi A, Bhattacharya N. Chikungunya virus infection in West Bengal, India. Indian J Med Microbiol 2016;34:213-5
|How to cite this URL:|
Chattopadhyay S, Mukherjee R, Nandi A, Bhattacharya N. Chikungunya virus infection in West Bengal, India. Indian J Med Microbiol [serial online] 2016 [cited 2019 Dec 12];34:213-5. Available from: http://www.ijmm.org/text.asp?2016/34/2/213/176839
| ~ Introduction|| |
The mosquito-borne Chikungunya virus (CHIKV) is an enveloped, linear, single stranded positive sense RNA virus of the family Togaviridae[1 ] transmitted - in Asia, including India, primarily by Aedes aegypti[2 ] and in the Indian Ocean Islands by the Aedes albopictus.  In Africa, the virus is, principally, spread by Aedes furcifer taylori, Aedes luteocephalus and Aedes africanus mosquito.  The term Chikungunya is derived from an African Makonde word "kungunyala," meaning "that which bends up" in reference to the stooped posture adopted as a result of the arthritic symptoms of the disease. 
The virus was first isolated from both humans and mosquitoes in the Newala district, Tanzania (formerly Tanganyika) in 1953.  Thereafter (CHIKV) has been repeatedly reported from numerous countries in Central and Southern Africa as well as in Senegal and Nigeria in West Africa.  In the recent years CHIKV has caused several epidemics in India, Philippines, Thailand, Cambodia, Vietnam, Myanmar and Srilanka and some island countries of the Indian Ocean  and is fast re-emerging as an important agent of public health importance.
In India, the virus was first isolated in 1963 in Kolkata  followed by epidemics in Chennai, Pondicherry and Vellore in 1964; in Visakhapatnam, Rajahmundry and Kakinada in Andhra Pradesh in 1965 and in Nagpur, also in 1965. The last officially recorded outbreak in India was reported in Barsi in Maharashtra in 1973. 
The disease re-emerged in India in October 2005 after remaining silent for nearly 32 years.  Andhra Pradesh was the first state to report this disease on December 2005.  Kerala was the worst affected state in 2007 with approx. 3.6 million fever cases.  Thereafter it has been repeatedly reported from 13 different states of India and has resulted in 1.4−6.5 million estimated cases across the country. 
The proposed study is an effort to assess the prevalence rate of CHIKV cases from the outpatients and inpatients of the different hospitals of West Bengal.
| ~ Materials and Methods|| |
Suspected cases complaining of fever of short duration (≤2 weeks) with/without joint pain and/or rash attending the OPD and in door of a tertiary care hospital in Kolkata were selected. Samples were also collected from various other tertiary care hospitals of Kolkata. Outbreaks samples were also collected from the various districts of West Bengal for a period of 6 months (April 2011-September 2011). The samples were tested serologically by MAC ELISA for IgM antibodies against CHIKV using the kit from National Institute of Virology (NIV) Pune. Hemagglutination inhibition (HI) test was also done using goose blood and the reagents prepared in the laboratory itself. Informed consent was taken from the patients/guardians and ethical committee approval was also taken.
In this community based cross-sectional study, a total of 206 (100 male and 106 female) patients clinically suspected to be suffering from CHIKV infection were enrolled. Subjects having short history of fever of ≤2 weeks with/without crippling arthralgia (joint pain) and/or rashes of both sexes and of all age-groups were included in the study.
Detailed history was taken and clinical examination was carried out. Five milliliters of venous blood was drawn aseptically. The serum was separated from the blood samples by centrifugation at 1500 rpm for 15 min and was stored at −20°C. Investigations to detect dengue specific IgM antibodies by ELISA was done using the kit from NIV Pune.Thick and thin blood smears were examined to exclude Malaria parasite.
A convalescent phase blood sample of 5 ml was also drawn from the same patients after an interval of 2 weeks for serological identification of HI antibody.
| ~ Results|| |
Of the 206 suspected Chikungunya cases, 76 (36.89%) were seropositive both by CHIKV IgM and HI assay. Male to female sex ratio was 1:1.17 (35 males and 41 females). Maximum number of positive cases (27-13 in males and 14 in females) was found in the age-group 31-40 years [Table 1].
Peak incidence of positive cases were seen in the month of August (32) and September (24) [Table 2].
Fever was the commonest symptom seen in 72 of 76 confirmed cases. Joint pain was present in 65 seropositive cases. The patients gave history that the pain started on the 1 st or 2 nd day of fever. It first involved the spine, both the small and big joints of both the extremities with no upper/lower limb predilection. The pain was usually bilateral and rarely there was unilateral involvement (three cases). Radiological screening of the joints did not reveal any significant abnormality.
Rash with fever was present in 40 out of 76 cases. The rashes were generalized, erythematous, maculopapular and nonpruritic in nature in both the trunk and extremities. Aphthous ulcers were also found to be present on the oral mucosa and the tongue.
Hemorrhage was not an important presenting symptom, present only in two seropositive cases. Anorexia, nausea and pain abdomen were the other associated minor symptoms.
Majority of the symptoms subsided within 3-5 days whereas joint pain and swelling persisted for more than 30 days. All the patients were treated symptomatically and no death was observed.
Fifteen cases required hospitalization; the rest were treated on an OPD basis. The duration of hospital stay ranged from 2 to 15 days.
Outbreak samples from about fourteen districts of West Bengal were also processed both by CHIKV IgM and HI assay [Table 3].
| ~ Discussion|| |
Of the 206 suspected cases, 76 (36.89%) were confirmed to be seropositive; seropositivity of 10.52% (8 positive cases out of 19 suspected cases) in 51-60 years age-group was found in our study compared to a survey conducted at Calcutta (now Kolkata) a decade ago. The Calcutta study had revealed 4.37% seropositivity in the age-group of 51-55 years. No antibody was detected in the younger population  in that study. In our study, maximum seropositivity (35.52%) (27 positive cases out of 58 suspected cases) was found in the age-group 31-40 years. This increased prevalence can be explained to be due to the resurgence of Chikungunya viral infection in India from 2005 onwards.
Ninety-five percentage of the patients reported of persistent joint pain and disabilities. Persistent arthralgia was first observed  in a study following a Chikungunya outbreak in 1952 on the Makonde Plateau along the border between Tanganyika and Mozambique. Long-term persistent arthralgia was also reported in a group of South African patients 3 years after the acute phase of illness in 1983.  The outbreak in Reunion islands also showed that resultant arthralgia persisted for 12-24 months. [ 14] In another study,  56 (63.8%) of the enrolled patients had persistent joint pain even 18 months after infection.
| ~ Conclusion|| |
The above study confirmed the emergence and spread of CHIKV infection in West Bengal, India. Though the disease is associated with low mortality, it leads to high morbidity. The health authorities and the community should therefore, keep a strict vigil for the early diagnosis of the illness.
We would like to thank the Director, School of Tropical Medicine, Kolkata for her kind support and allowing us to conduct the study.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| ~ References|| |
Lahariya C, Pradhan SK. Emergence of chikungunya virus in Indian subcontinent after 32 years: A review. J Vector Borne Dis 2006;43:151-60.
Mohan A, Kiran DH, Manohar IC, Kumar DP. Epidemiology, clinical manifestations, and diagnosis of chikungunya fever: Lessons learned from the re-emerging epidemic. Indian J Dermatol 2010;55:54-63.
Khan AH, Morita K, Parquet Md Mdel C, Hasebe F, Mathenge EG, Igarashi A. Complete nucleotide sequence of chikungunya virus and evidence for an internal polyadenylation site. J Gen Virol 2002;83(Pt 12):3075-84.
Powers AM, Brault AC, Tesh RB, Weaver SC. Re-emergence of chikungunya and O'nyong-nyong viruses: Evidence for distinct geographical lineages and distant evolutionary relationships. J Gen Virol 2000;81(Pt 2):471-9.
Best M, Graham ML, Leitner R, Ouellette M, Ugwu K, editors. Laboratory Biosafety Guidelines. 3 rd
ed. Canada: Public Health Agency of Canada; 2004.
Ramana KV, Prakash GK. Mystery behind emergence and re-emergence of Chikungunya virus. Ann Trop Med Public Health 2009;2:1-3.
Yergolkar PN, Tandale BV, Arankalle VA, Sathe PS, Sudeep AB, Gandhe SS, et al.
Chikungunya outbreaks caused by African genotype, India. Emerg Infect Dis 2006;12:1580-3.
Ravi V. Re-emergence of chikungunya virus in India. Indian J Med Microbiol 2006;24:83-4.
Kumar NP, Joseph R, Kamaraj T, Jambulingam P. A226V mutation in virus during the 2007 chikungunya outbreak in Kerala, India. J Gen Virol 2008;89(Pt 8):1945-8.
Srikanth P, Sarangan G, Mallilankaraman K, Nayar SA, Barani R, Mattew T, et al.
Molecular characterization of chikungunya virus during an outbreak in South India. Indian J Med Microbiol 2010;28:299-302.
Neogi DK, Bhattacharya N, Mukherjee KK, Chakraborty MS, Banerjee P, Mitra K, et al.
Serosurvey of chikungunya antibody in Calcutta metropolis. J Commun Dis 1995;27:19-22.
Robinson MC. An epidemic of virus disease in Southern Province, Tanganyika Territory, in 1952-53. I. Clinical features. Trans R Soc Trop Med Hyg 1955;49:28-32.
Brighton SW, Prozesky OW, de la Harpe AL. Chikungunya virus infection. A retrospective study of 107 cases. S Afr Med J 1983;63:313-5.
Grivard P, Le Roux K, Laurent P, Fianu A, Perrau J, Gigan J, et al.
Molecular and serological diagnosis of chikungunya virus infection. Pathol Biol (Paris) 2007;55:490-4.
Borgherini G, Poubeau P, Jossaume A, Gouix A, Cotte L, Michault A, et al.
Persistent arthralgia associated with chikungunya virus: A study of 88 adult patients on reunion Island. Clin Infect Dis 2008;47:469-75.
[Table 1], [Table 2], [Table 3]