|Year : 2013 | Volume
| Issue : 3 | Page : 189-196
Outbreak investigation and intervention measures following viral hemorrhagic fever in rural Kutch (Gujarat)
Kishor M Dhaduk, Kapiil M Gandha, Sumit V Unadkat, Naresh R Makwana, Dipesh V Parmar, Sudha Yadav
Department of Community Medicine, Shri M.P. Shah Government Medical College, Jamnagar, Gujarat, India
|Date of Web Publication||25-Oct-2013|
Kishor M Dhaduk
Department of Community Medicine, Shri M.P. Shah Government Medical College, Jamnagar, Gujarat
Source of Support: None, Conflict of Interest: None
Background: To describe detailed epidemiological analysis of an outbreak of suspected Crimean-Congo hemorrhagic fever (CCHF) based on available clinicopathological and verbal autopsy findings of the cases and epidemiological intervention taken for prevention and control of the same in a rural setting of India. Aims: To define clinical syndrome, to find-out probable etiology, source of infection, mode of transmission and to develop a control and prevention strategy to halt further spread of unknown fatal febrile illness. Settings and Design: It was an outbreak investigation in affected small village of Gujarat, applying few principles of descriptive epidemiology in rural settings. Materials and Methods: Various information obtained by in-depth interviews, verbal autopsy tools, available medical records and house to house active case finding survey. Statistical Analysis: Microsoft Excel 2007 was used for statistical analysis. Results: The relevant information revealed that it as clustering of unknown hemorrhagic fever in households infested by hard tick population with a potential to further outbreak in and around nearby area. All secondary cases had strong epidemiological link with the index case. The illness was characterized by high grade fever with chills, headache and body-ache for short duration of 3-6 days followed by varying degree of hemorrhagic tendency, hepatic and renal involvement. The case fatality rate was very high (60%) and probable length of the incubation period was 9-15 days. Conclusions: It was a probable outbreak of a viral hemorrhagic fever, clinically compatible with CCHF cases. Effective removal of hard tick population from the village by Malathion spray had played a significant role in control and prevention of further cases.
Keywords: Malathion, outbreak, thrombocytopenia, tick, unknown febrile illness, verbal autopsy
|How to cite this article:|
Dhaduk KM, Gandha KM, Unadkat SV, Makwana NR, Parmar DV, Yadav S. Outbreak investigation and intervention measures following viral hemorrhagic fever in rural Kutch (Gujarat)
. Int J Health Allied Sci 2013;2:189-96
|How to cite this URL:|
Dhaduk KM, Gandha KM, Unadkat SV, Makwana NR, Parmar DV, Yadav S. Outbreak investigation and intervention measures following viral hemorrhagic fever in rural Kutch (Gujarat)
. Int J Health Allied Sci [serial online] 2013 [cited 2023 Mar 29];2:189-96. Available from: https://www.ijhas.in/text.asp?2013/2/3/189/120588
| Introduction|| |
During the past few years, a large number of arthropod-borne viruses (arboviruses) have been isolated from sick persons, animals and arthropods throughout the world. Number of arboviruses known in India has risen from two (dengue and sand fly fever) in 1951 to over 40 in 1975.  On a global basis, ticks transmit a number of pathogenic organisms such as protozoans, rickettsia, spirochetes and viruses than any other arthropod vector group and are among the most important vectors of diseases affecting livestock, humans and companion animals.  Serological surveys in different parts of India revealed antibodies to tick borne viruses in human and animal particularly in cattle in Kutch district and Saurashtra region. 
Tick larval population builds up in monsoon month, but remains dormant under forest litter and becomes suddenly active as a nymph when the litter dries up in post monsoon months October to December. Epidemic of tick borne diseases coincides with nymphal activity; hence, nymphs are considered as the most important stage for human transmission [Figure 1]. 
In the absence of virological diagnostic facilities, a firm diagnosis based on clinical observations is extremely difficult to make, particularly when isolated cases occur. In epidemic situations, a clinical diagnosis may be made easier when several patients exhibit similar symptoms. The source of infection may also be recognized, which can often be helpful in arriving at a diagnosis. In their early stages, many virus infections have very similar symptoms, often appearing as non-specific "influenza-like" illnesses with fever, headache and generalized joint and muscle pains. In tropical areas, diagnosis is difficult because the signs can be confused not only with those of other virus infections, but with protozoal and bacterial infections such as malaria and typhoid fever. In these circumstances, the trial use of antimalarial drugs and antibiotics is often justified.  So, for an effective control and future prevention of an unusual event in any area, disease surveillance is needed to recognize cases or a cluster of cases, to identify a high-risk group or geographic areas, with a view to initiate an effective response in a timely manner, to prevent transmission of disease or to reduce morbidity and mortality. 
During the month of December 2009, Chief District Health Officer (CDHO), Kutch reported three deaths among five cases within 6-10 days of acute fatal febrile illness and presence of hard tick infestation both intra- and para-domestically in Mota-Tindalva village of subcenter Sahi and Gagodar Primary Health Center (PHC) of Rapar Taluka of Kutch District of Gujarat, India. Rapid response team (RRT) from M.P. Shah Medical College Jamnagar deputed to investigate the situation. This article has discussed available clinical and laboratory finding of the patients and epidemiological intervention taken for control of the acute fatal febrile illness Crimean-Congo hemorrhagic fever (CCHF?) and tick control.
| Materials and Methods|| |
It was an outbreak investigation.
The epidemiological investigation and control activities were carried out by deputed RRT members and technical staff of health and family welfare department of Gujarat government in a rural setting of India.
Selection of participants
We interviewed the village Sarpanch, local leaders and PHC staff of Gagodar PHC (ANM, MPW, MPHS, MOs) and collected various relevant information about whether there was unusual rise in fever cases of similar fatal illness and/or deaths in man and/or in any domestic and/or para-domestic animals, dietary habits of population, major migration and/or immigration of human population, appearance of new vectors, change in source/quality of drinking water and amount of rainfall in the village and in nearby villages during the last 1 year from the occurrence of the index case.
Methods of measurement
Qualitative as well as quantitative tools were applied to get the necessary information from the participants. The RRT (Epidemiologist, Physician and Microbiologist) visited the village on 18 th December 2009. For the investigation of the situation, we were provided and supported with state entomological team and district malaria control team along with insecticidal spray squads.
Data collection and processing
Active search for suspected case and blood sample collection, collection of environmental information and chlorination of household water using chlorine tablets, performed by the house to house visit of all dwellings of the village by five teams, (each consisting one ANM, MPW, MO-PHC) by Oral questionnaire method in a pretested proforma containing information of new suspected human case, presence of mosquito and other vector breeding and any other specific event or history of exposure.
Microsoft Excel 2007 software was used for the analysis of data and preparation of graph.
Informed consent was taken prior to enrollment of the study participants. As the outbreak investigation and control of fatal illness within possible short time period was our prime priority and it was a part of the duty ordered from health and family welfare department of Gujarat government, so it was not mandatory to get the institutional ethical clearance. However, we took utmost care for the data to remain anonymous and confidential.
Formulation of operational case definition based on findings of verbal autopsy
Information regarding sequence of events occurred in the life of three deceased cases during the last 1 year from the index case was collected from close relatives by verbal autopsy. All available medical records and reports of these cases were reviewed.
Based on verbal autopsy finding we formulated Operational definition of "a case" of the unknown hemorrhagic fever under study as follow:
- Any death in the Mota-Tindalva or in the nearby village
- Any fever case with at least one of the following.
- H/O hard tick bite and/or presence of Hard tick in house
- Jaundice and/or Hepatomegaly and/or splenomegaly
- Epigastric pain with vomiting and/or diarrhea.
- Bleeding tendency (hematemesis, Hematuria, gum bleeding, epistaxis, Blood in stool, hemoptysis)
- Anuria or oliguria
- Severe pallor.
Control of tick population
On 18 th December 2009, residual spray of Malathion 5% water-based emulsion  sprayed in both indoor and outdoor places of the entire village for control of hard tick breeding.
Collection of blood samples
On the 22 th December 2009, we have sent three human sera samples; two from 2 nd deceased and 5 th case and one from close contact of 2 nd and 3 rd deceased, 18-year-old son of these deceased cases, to National Centre for Disease Control laboratory, New Delhi for identification of the causative agent of unknown fatal illness.
| Results|| |
It was a cluster of unknown hemorrhagic fever (?VHF) cases during 29 November 2009 to 14 December 2010 in Mota-Tindalva Village of Gagodar PHC, Rapar Block, Kutch District, Gujarat and declared as an outbreak by the district health authority.
Mota-Tindalva Village, situated 7 km in east from Rapar surrounded by grounds and farms and belongs to Kutch district, which has desert geography. Total population of the village was about 754 and they were residing in 152 households. All of them were vegetarians in diet and were either farmers, cattle rearers or laborers. There was neither any major migration and/or immigration of human population from/to a particular area having such illness in endemic form, nor any change in usual source/quality of drinking water in the village since 1 year before the index case.
Animal population and vectors
Bullocks, cows, buffaloes, sheep, goats and horses were common domestic animals in the majority of the house hold. During December 2009, it was a very cold weather (temperature 10-15°C) with a history of heavy rainfalls than an average during last monsoon.
In last monsoon, there was history of appearance of hard tick breeding and its animal infestation after death of a blue bull (Neel gai) in last monsoon about < 1 km in the east of the village, but there was no reported death in domestic animal population. At the time of investigation, infestations of hard tick were observed in 35/152 (23%) houses among which many of them have cattle infestation also. Most of the ticks were in nymphal stage of the developmental cycle. There was also presence of Aedes mosquito larvae, but in only two separate domestic water containers of two houses. Most of all cases (4/5) belonged to those households, which had showed infestation with tick population while only one case was found in households, which were free from tick infestation. However, this case worked as a laborer in the farm of the index case.
There was no evidence of unusual rise in fever cases of similar fatal illness and/or deaths in humans of the village or in nearby villages during the last 1 year before the occurrence of the index case.
Description of human cases
The index case
The initial case identified was a 35-year-old male working as a farmer (index case and head of family of five members - A retired father, wife and two children) who presented on December 1 st , 2009 with 3 days history of an acute febrile illness characterized by fever, chills, vomiting and headache followed by jaundice and hemorrhagic symptoms (hematemesis, bleeding from co-existing wound on Rt. dorsum of palm), to private physician at Modasa, Sabarkantha, where he was given intravenous (IV) fluids and empirical antibiotic treatment and referred to civil Hospital, Ahmadabad. On the way to civil Hospital, patient developed convulsion and was declared as dead in the civil Hospital, Ahmadabad [Table 1]. Surprisingly, there was no affection of any other member of the family of the index case residing in a household, which was heavily infested with tick population.
|Table 1: Description and characteristics of study cases of an unknown illness |
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After the period of 10 days, sister in law and elder brother of the index case, both had visited the index case as well as attended the funeral and post funeral procedure of the index case, developed fever with chills on 08-12-09 and 09-12-09 respectively, followed by epigastric pain, jaundice and bleeding tendency in various form. This couple was residing with their family in a separate household, which also was infested with ticks and was approximately 40 m from the household of the index case. Initially, the wife was brought to Community Health Center (CHC) Rapar where so many hard ticks were removed from her body and she was diagnosed as having thrombocytopenia with negative dengue and malaria antigen test and referred to higher center. Then, the wife was treated by IV whole blood, platelet rich plasma and broad spectrum antibiotic, but unfortunately she died on 7 th day of illness owing to disseminated intravascular coagulation, severe anemia leading to multiple organ failure in private physician Hospital at Mota Chiloda. The husband was treated initially in outpatient department of CHC Rapar, Kutch by oral medication and later on from 6 th day of onset of the illness developed severe diarrhea with blood, vomiting and jaundice for which he was admitted in civil Hospital, Rajkot where he died on 10 th day of the illness [Table 1].
Later on in next 4 days, two other cases of high grade fever with chills occurred on 10 th and 14 th December 2009 respectively. One of them developed Epigastric pain and vomiting for that he was treated by IV fluids and antibiotics for 14 days successfully in civil Hospital Rajkot while the last case recovered from fever after 10 days' treatment given by a private physician in Modasa [Table 1].
Laboratory features of the cases
Although there was variation in place of treatment, treating physicians and the laboratory investigation patterns, most of the cases has common finding of severe thrombocytopenia (4/5 cases), hepatic involvement with serum glutamic pyruvic transaminase (SGPT) 1250 International Unit/L (1/5, other not investigated for this), leukocytosis (2/5 cases) or leucopoenia (3/5 cases) and anemia of varying degree [Table 2].
|Table 2: Available biochemical and pathological laboratory data of the study cases |
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National Center For Disease Control, New Delhi laboratory report of three human sera samples (one from 2 nd deceased and one from 5 th case and one from close contact of 2 nd and 3 rd deceased, 18-year-old son of these deceased cases) were negative for chikungunya, dengue and leptospirosis. 
Calculation of the incubation period from serial interval
longest serial interval between the onset of first and last case was 15 days while shortest serial interval between the onset of 1 st and 2 nd case was 9 days [Figure 2]. Therefore, if we consider the index case as the primary source of infection, probable length of the incubation period of this unknown illness was 9-15 days.
Presence of hard tick infestation was found in 35 households, which yielded 4 cases of high grade fever with thrombocytopenia among 169 at risk human population and 3 out of these 4 cases succumbed. So, incidence rate of illness in at risk household was calculated 2.37%, but case fatality was 75%. One case occurred in a farm-laborer working in the farm of the index case, survived the deadly illness. Household of this farm laborer was not showed evidence of any tick infestation. Thus, the incidence rate of illness in non-risk household was calculated as 0.17% (1 × 100/585) with no fatality. Furthermore, the overall incidence rate for the village was 0.66% with 60% case fatality rate. The observed difference among incidence rate and case fatality rate between exposure and non-exposure groups was statistically significant [Table 3].
|Table 3: Comparison of incidence rate based on the presence of tick infestation in households |
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| Discussion|| |
The presence of fever, malaise and headache concomitant with laboratory findings of leucopoenia and thrombocytopenia is a common clinical picture for zoonotic diseases of bacterial and viral origin, but detailed analysis of virus outbreaks is often limited by the lack of appropriate high-containment facilities required for virus isolation. ,
It was an outbreak of unknown viral hemorrhagic fever (VHF) cases with three deaths among 5 cases (60% case fatality rate) in a very small village of Gujarat during November-December 2009. The illness was initially characterized by acute onset of fever, chills, anorexia, headache and body ache followed by severe manifestation of multiple organ involvement after a period of 3-6 days i.e., liver (epigastric pain, vomiting, appearance of jaundice), kidney (oliguria/anuria), Gastro Intestinal Tract (GIT) (diarrhea) and blood clotting system (varying degree of hemorrhages from a different site). Aradaib et al., Nosocomial Outbreak of CCHF (study of ten patients), Sudan, May 2010 and Mourya et al., VHF (study of five patients) in Ahmadabad, India, 2010-2011, in their studies, demonstrated similar sign and symptoms among the patients of Nosocomial outbreak of CCHF. , The finding of symptom analysis in the present study also matches with Notice to Readers Update: Management of Patients with Suspected VHF-United States 1995. 
In the present study, even with variation in places of treatment received, most of the cases has common finding of severe thrombocytopenia (4/5 cases), hepatic involvement with SGPT 1250 IU (1/5, other not investigated for this), leucocytosis (2/5 cases) or leucopoenia (3/5 cases) and anemia of varying degree. While in a study of Ergonul et al. on Characteristics of patients with CCHF in a Recent Outbreak in Turkey and Impact of Oral Ribavirin Therapy, 2002-2003, all patients had leukopenia, thrombocytopenia and elevated levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactic dehydrogenase and creatinine phosphokinase. 
Any of the following clinical pathologic values during the first 5 days of illness were found to be >90% predictive of fatal outcome in a series of South African CCHF patients: leukocyte counts <(10 × 10 9 )/L, platelet counts <(20 × 10 9 )/L, AST > 200 U/L, ALT > 150 U/L, activated partial thromboplastin time > 60 s, and fibrinogen <110 mg/L.  According to these criteria, most of our patients (4/5 cases) have at least one or more of the risk factors described above, the overall death rate was very high (60%) and 75% of severe cases died within 4-10 days of illness.
According to criteria for clinical diagnosis of CCHF by Swanepoel et al., a total score of 12 points or more in VHF constitutes an indication for treating a patient as a case of CCHF [Table 4].  In the present study, all deceased cases had a total score of 14 points or more [Table 2] and [Table 4] and none of them had been treated with Ribavirin as per available medical records. Otherwise, they could have been saved if timely imperative Ribavirin therapy had been initiated. 
|Table 4: Criteria for clinical diagnosis of Crimean - Congo hemorrhagic fever - 1987 |
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Overall case fatality was very high (60%) in our study as compared to study of Ergonul et al. in Turkey in which reported case fatality of VHF cases in the medical literature, was the lowest case-fatality rate of CCHF 2.8%. This could be explained, by the role of vigorous supportive therapy and the administration of Ribavirin within 24 h after admission to 8 patients in the later study or by a geographic variation in viruses.  Not a single case in the present was treated with Ribavirin.
Within a month, there were two serum samples referred to NIV, Pune from Rajkot, Gujarat, from patients suspected for viral hemorrhagic fever in the month of February 2010 and both had succumbed to the unknown infection. Later on the same samples were included in the study of Mourya et al. (2010-11) for retrospective analysis and both were found positive for Crimean-Congo hemorrhagic fever virus (CCHFV) by quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and RT-PCR.  The geographical distribution of CCHF cases corresponds closely with the distribution of principle tick vectors, i.e. species of Hyaloma. Nevertheless, other Ixodid ticks can also support CCHFV infection moreover some species of Hyaloma, Dermacentor and Rhipicephalus genera have also been shown capable of transstadial and transovarial transmission. The virus is transmitted to humans through the bite of Ixodid ticks or by contact with blood or tissues from infected livestock, the latter being the most significant transmission route to humans in Iran. In contrast to human infection, infections in the live stocks generally result in unapparent or sub clinical disease.  These are sufficient evidence of CCHF endemicity in Gujarat during 2010.
Mourya et al. stated that the likely source of CCHFV was identified as virus infected Hyalomma ticks and livestock at the rural village residence of the primary case.  Similarly in the present study, there were strong evidences of epidemiological link in between the index case and secondary cases [Table 2].
There are many different aspects that affect the prevalence criteria for CCHF, which still remained unknown. It is clear that controlling tick populations in endemic regions will play an important role in prevention and incidence of CCHF disease.  This could explain successful removal of suspected vector (hard tick) population by Malathion spray and dramatic cessation of the cases in the present study.
| Recommendation|| |
- Unusual rise or appearance of a new arthropod vector in any geographical area should be considered serious and must be a part of routine disease surveillance reporting system so that the triggering event can be anticipated timely and taken care by public health delivery system before the occurrence of morbidity or mortality. This is possible in India by Integrated Disease Surveillance Project reporting
- Any animal carcass(es) or cadaver(s) can become "Hot Spot" and provide a breeding ground to hematopagus arthropod vector. So, such cascara should be burnt by efforts from community members
- Close contacts of those succumbed in VHF, domestic cattle population and prevalent tick population needs to be screened for Anti-CCHF Immunoglobulin G to provide retrospective evidence of confirmed CCHF infection
- Clearly, Viral Hemorrhagic Fevers including CCHF are present in Guarat and paid a heavy toll in the form of life of medical care providers in recent past by nosocomial spread.  So, Physicians should consider epidemiological history of hemorrhagic fever cases and should consider CCHF in their differential diagnosis in the region. They should also ensure about universal work precaution while providing care to such patients. In addition, efforts to provide appropriate personal protective supplies and training to medical staff should be increased to help minimize risk for caregivers to prevent nosocomial spread.
| Acknowledgments|| |
We acknowledge the support and cooperation from State Entomology team, Dr. Dinesh Dabhi CDHO Kutch and DMO of the Kutch district and health workers (MPWs) of concern PHCs. We are also very much thankful to the Department of Health and Family Welfare-Government of Gujarat for the opportunity to do the field study. We also dedicate the work towards those who lost their life due to yet -to-be-diagnosed viral hemorrhagic fever.
| References|| |
|1.||Park K. Other arboviral diseases. In: Park's Textbook of Preventive and Social Medicine. 19 th ed. Jabalpur (India): Banarsidas Bhanot publishers; 2007. p. 237-41. |
|2.||Ghosh S, Azhahianambi P, Yadav MP. Upcoming and future strategies of tick control: A review. J Vector Borne Dis 2007;44:79-8. |
|3.||Telford H. Work and Herold Trapido. Kyasanur Forest Disease: A new infection of man and monkeys in tropical India by a virus of the Russian spring-summer complex. Proceeding of the 9 th Pacific Congress of Pacific Science Association, 1957; Chulalongkom University, Bangkok, Thailand. Secretariat, Ninth Pacific Science Congress, Department of Science, Bangkok, Thailand; 1962. p. 80-5. |
|4.||Simpson DI. Hamorrhagic fever of man. WHO Bulletin 1978;56:820-32. |
|5.||Mandal NK, Mukhopadhyay DK, Saren AB, Panja TK, Sinha N, Biswas AB. Investigation of death due to Fever in patrasayer block in the district of bankura, west bengal. Indian J Community Med 2009;34:374-5. |
|6.||World Health Organization. Vector control: Methods for use by individuals and communities. Geneva: WHO Library Catalogue; 1997. p. 263-75. |
|7.||Arbovirus Laboratory Report. Director General of Health Services, National Centre for Disease Control, Zoonotic Division, Arbovirus Laboratory, Shamnath Marg, New Delhi; 2010. Fax No. 23922677. |
|8.||Ergonul O, Celikbas AK, Dokuzoguz B, Eren S, Baykam N, Esener H. Characteristics of patients with Crimean-Congo hemorrhagic fever in a recent outbreak in turkey and impact of oral ribavirin therapy. Oxford J Clin Infect Dis 2004;39:284-7. |
|9.||Aradaib IE, Erickson BR, Mustafa ME, Khristova ML, Saeed NS, Elageb RM, et al. Nosocomial outbreak of Crimean-Congo hemorrhagic fever, Sudan. Emerg Infect Dis 2010;16:837-9. |
|10.||Mourya DT, Yadav PD, Shete AM, Gurav YK, Raut CG, Jadi RS, et al. Detection, isolation and confirmation of Crimean-Congo hemorrhagic fever virus in human, ticks and animals in Ahmadabad, India, 2010-2011. PLoS Negl Trop Dis 2012;6:e1653. |
|11.||Centers for Disease Control and Prevention (CDC). Update: Management of patients with suspected viral hemorrhagic fever - United States. MMWR Morb Mortal Wkly Rep 1995;44:475-9. |
|12.||Swanepoel R, Gill DE, Shepherd AJ, Leman PA, Mynhardt JH, Harvey S. The clinical pathology of Crimean-Congo hemorrhagic fever. Rev Infect Dis 1989;11 Suppl 4:S794-800. |
|13.||Swanepoel R, Mynhardt JH, Harvey S. Criteria for clinical diagnosis of Crimean-Congo haemorrhagic fever, 1987. Available from: http://www.xa.yimg.com/kq/groups/18156219/1652059995/name/CCHF_criteria_for_clinical_diagnosis.pdf. [Last accessed on 2013 Jan 29]. |
|14.||Chinikar S, Ghiasi SM, Hewson R, Moradi M, Haeri A. Crimean-Congo hemorrhagic fever in Iran and neighboring countries. J Clin Virol 2010;47:110 -4. |
[Figure 1], [Figure 2]
[Table 1], [Table 2], [Table 3], [Table 4]