Amiya Kumar Hati

Concurrent dengue and malaria in an area in Kolkata

OBJECTIVE To establish the nature and extent of dual dengue and malaria infections in an endemic area through a longitudinal study. METHODS A prospective study was conducted from August 2005 to December 2010 to document the nature and extent of concurrent dengue and malaria infections in an area in central Kolkata, endemic both for dengue and malaria. RESULTS Of 2 971 suspected cases of dengue fever, in 605 (20.36%) persons dengue infection was detected, of whom 46 (7.60%, 46/605) patients (40 and 6 suffered from secondary and primary dengue fever respectively) were simultaneously suffering from malaria (28 and 18 were infected with Plasmodium vivax (P.vivax) and Plasmodium falciparum (P. falciparum) respectively, such dual infections of dengue and malaria were detected in all the years of the study period, except 2007, indicating intense transmission of both dengue and malaria in the study area, and the phenomenon was not an isolated one, the rate of concomitant infections ranged from 25% in 2009 to 4.9% in 2005. Out of total population surveyed, 1.54% (46/2 971) had concurrent dengue and malaria infection. CONCLUSIONS These findings added a new dimension in diagnosis, treatment, epidemiology and control of dengue and malaria. The possible risk of concurrent dengue and malaria infections should always be kept in mind in endemic areas for early diagnosis employing modern technology and prompt and effective treatment to avoid serious complications.

Double Mutation in the pfmdr1 Gene Is Associated with Emergence of Chloroquine-Resistant Plasmodium falciparum Malaria in Eastern India

ABSTRACT Malaria is a major public health problem in tropical and subtropical countries, including India. This study elucidates the cause of chloroquine treatment failure (for Plasmodium falciparum infection) before the introduction of artemisinin combination therapy. One hundred twenty-six patients were randomized to chloroquine treatment, and the therapeutic efficacy was monitored from days 1 to 28. An in vitro susceptibility test was performed with all isolates. Parasitic DNA was isolated, followed by PCR and restriction digestion of different codons of the pfcrt gene (codons 72 to 76) and the pfmdr1 gene (N86Y, Y184F, S1034C, N1042D, and D1246Y). Finally, sequencing was done to confirm the mutations. Forty-three (34.13%) early treatment failure cases and 16 (12.69%) late treatment failure cases were observed after chloroquine treatment. In vitro chloroquine resistance was found in 103 isolates (81.75%). Twenty-six (60.47%) early treatment failure cases and 6 (37.5%) late treatment failure cases were associated with the CVMNK-YYSNY allele (the underlined amino acids are those that were mutated). Moreover, the CVIEK-YYSNY allele was found in 8 early treatment failure (18.60%) and 2 late treatment failure (12.5%) cases. The presence of the wild-type pfcrt (CVMNK) and pfmdr1 (YYSNY) double mutant allele in chloroquine-nonresponsive cases was quite uncommon. In vivo chloroquine treatment failure and in vitro chloroquine resistance were strongly correlated with the CVMNK-YYSNY and CVIEK-YYSNY haplotypes (P < 0.01).

Association between prevalence of pyrimethamine resistance and double mutation in pfdhfr gene in West Bengal, India

Abstract Objective To find whether antifolate drug (pyrimethamine) resistance has occurred in the two malaria endemic zones (Kolkata and Purulia) of West Bengal, India. Methods Parasitic bloods were collected from patients of Kolkata and Purulia, in vitro susceptibility test were performed in those 90 isolates. Now parasitic DNA was isolated by phenol chloroform extraction method and then polymerase chain reaction and restriction fragment length polymorphism analysis of different codons of pfdhfr gene (51, 59, and 108) were assessed in Plasmodium falciparum isolates from patients in India. Results Among 45 isolates from Kolkata dhfr mutant isolates at codons 108, 51 and 59 were found in 71.11%, 100% and 15.55% isolates respectively while in Purulia mutation found in those codons were 42.22%, 57.77% and 0%, respectively. In Kolkata, the isolate having double mutation (N108 + 51I) were resistant to pyrimethamine (P Conclusions Our present findings implicate that due to enormous drug (pyrimethamine) pressure double mutation with dhfr S108N/T and N51I was highly correlated (P dhfr mutations was strongly correlated to resistance to pyrimethamine.

TRANSMISSION OF VIABLE MYCOBACTERIUM LEPRAE BY AEDES AEGYOTU FROM LEPROMATOUS LEPROSY PATIENTS TO THE SKIN OF MICE THROUGH INTERRUPTED FEEDING

Female Aedes aegypti which took partial blood meals from the skin lesions of untreated lepromatous leprosy (LL) patients were then allowed to continue feeding on 72-96-hr-old Swiss albino suckling mice (Rockefeller strain). The bitten portion of skin was removed, divided into two parts and processed for the extraction of bacilli by two different methods using chloroform and petroleum ether. The proboscis of some of the fed mosquitoes was dissected out and examined for viable bacilli (stained by fluorescein diacetate and ethidium bromide) and acid-fast bacilli (AFB). Out of 50 probosces dissected 45 were found positive for AFB, with bacillary counts ranging up to 246 (average 40.20 +/- SD 41.80) per proboscis. The average percentage of viable bacilli (green solid) in the probosces immediately after feeding on LL patients was 43.90 and thereafter it decreased gradually to 3 on the seventh day. In the petroleum ether extract of mouse skin viable bacilli were observed in numbers up to 37 (average 15.25 +/- SD 10.25) per smear. The number of fluorescing bacilli (green and red) correlated with the total number of AFB.

Association between Prevalence of Chloroquine Resistance and Unusual Mutation in pfmdr-I and pfcrt Genes in India

This study deals with the underlying causes of failure of chloroquine in the treatment of Plasmodium falciparum infection in some malaria-endemic regions of India. Samples were collected from 141 patients in Purulia from March of 2007 to April of 2008. In vitro drug susceptibility tests, parasitic DNA isolation followed by polymerase chain reaction, and restriction fragment-length polymorphisms of different codons of the pfcrt gene (76) and pfmdr-I genes (86, 1042, and 1246) were assessed. The responses of 141 patients to chloroquine were determined. Prevalence of double pfmdr-I (58.16%) mutation (86Y+1246Y) and some (14.89%) single pfcrt mutations with triple pfmdr-I mutation (76T+86Y+1042D+1246Y) were found. Interestingly, double pfmdr-I mutation (86Y and 1246Y codons) was observed with the early treatment failure cases. These results show, for the first time in India that in vitro chloroquine resistance and in vivo chloroquine treatment failure were caused by double pfmdr-I (P < 0.001) mutation.

Serological diagnosis of dengue in laboratory practice in Kolkata

PURPOSE To find out the most suitable serological investigative procedures to diagnose dengue cases effectively in the laboratory practice identifying primary and secondary cases as well as period of suffering. MATERIALS AND METHODS Dengue suspected cases sent to the laboratory in 2012 in central Kolkata by the local physicians were categorised into seven panels according to the investigations asked for such as (1) only dengue-specific NS1 antigen (2) only IgM antibodies, (3) NS1+IgM+IgG antibodies, (4) only IgM and IgG, (5) NS1+IgM, (6) NS1+IgG and (7) only IgG. RESULTS Out of 1892 suspected cases, dengue was diagnosed in 725 (38.3%). Through panels I, II, III, IV, V, VI and VII, it was possible to diagnose dengue in (I) 35.98% (435/1209), (II) 37.5% (24/60), (III) 49% (173/354), (IV) 30.8% (68/221), (V) 60.5% (23/38), (VI) 40% (2/5) and (VII) 0 of cases respectively. Detail information such as confirmed diagnosis, duration of the disease (whether early or prolonged) and classification of primary and secondary dengue in such early or prolonged stages would only be possible in panel III, which information would be helpful for effective monitoring and treatment of dengue patients. In all other panels, merely fragmentary information would be obtained. CONCLUSIONS Serodiagnostic tests dengue-specific NS1 antigen and IgM and IgG antibodies when conducted simultaneously would be able to diagnose confirmed dengue cases categorising primary and secondary dengue along with the duration of the disease, whether early or prolonged.

Retrospective analysis of dengue specific IgM reactive serum samples

Objective To conduct a retrospective analysis of dengue cases in Kolkata, on the basis of presence of anti-dengue IgM in their sera and presence or absence of anti-dengue IgG and dengue specific Non structural 1 (NS1) antigen in each of the serum sample.

Progressive increase in point mutations associates chloroquine resistance: Even after withdrawal of chloroquine use in India

Chloroquine (CQ) is highly effective against P. vivax, due to the rapid spread of CQ resistance in P. falciparum parasites; it is no longer the drug of choice against P. falciparum. This study elucidates the scenario of chloroquine efficacy at times that coincided with a new drug policy and especially assessed the chloroquine resistant molecular markers after withdrawal of chloroquine in Kolkata and Purulia, two malaria endemic zones of West Bengal, India. In vitro CQ susceptibility was tested in 781 patients with P. falciparum mono infections between 2008 and 2013, of which 338 patients had received CQ in 2008–2009. Genotyping of the pfcrt and the pfmdr1 gene was carried out in all isolates. Early treatment failure was detected in 114 patients {43 (31·39%) from Kolkata and 71 (35·32%) from Purulia} while recrudescence was identified in 13 (9.49%) and 17 (8.46%) patients from Kolkata and Purulia respectively. In vivo chloroquine resistance was strongly associated with CVMNT-YYSNY (p < 0.01) and SVMNT-YYSNY (p < 0.05) allele in Kolkata. In Purulia chloroquine resistance was associated with CVMNK-YYSNY (P < 0.005), SVMNT-YYSNY (P < 0.01) allele. The proportion of in vitro chloroquine resistance increased in subsequent years to 87.23% and 93·10% in 2013, in Kolkata and Purulia, respectively. Isolates with SVMNT-YFSND, SVMNT-YFSNY, CVIET-YFSND and CVIET-YYSNY haplotypes increased gradually (p < 0.05) from 2010 to 2013, leading to a rise in IC50 (p < 0.05) of chloroquine. An increase in in vitro chloroquine resistance and candidate gene mutations even after five years of chloroquine withdrawal against P. falciparum calls for synchronized research surveillance and proper containment strategies.

Concurrent Infections of Three Mosquito Borne Diseases-Dengue, Chikungunya and Malaria

Kolkata, India is endemic for mosquito borne diseases like dengue, chikungunya and malaria. For monitoring, altogether 252 serum samples of fever cases were examined for dengue specific NS1 antigen and IgM and IgG antibodies and chikungunya specific IgM antibody. Their blood samples were also tested for malarial parasites. Out of 252 cases, 15 (5.95%), 16 (6.34%) and 18 (7.13%) were infected with dengue, chikungunya and malaria respectively. Amongst 15 dengue cases 10 (3.96%) were positive for both dengue IgM and IgG antibodies and 5 (1.98%) for NS1 antigen. Out of 18 malaria victims 14 (5.55%) and 4 (1.58%) were positive for Plasmodium vivax and Plasmodium falciparum respectively. During the present study, one case of concurrent infections of dengue and chikungunya and another case of concurrent infections of dengue, chikungunya and falciparum malaria were detected. Detail case report of the later has been described. This is the first ever report of concurrent infections of dengue, chikungunya and malaria.

Ultrasonic measurement of the liver in search of Plasmodium vivax cases that relapse

Abstract Objective To find out whether relapse can be differentiated in vivax patients. Methods Sixty three people suffering from vivax were taken and ultrasonography was done. Results Among 63 persons, previous history of vivax was obtained in 51. Out of remaining 12, previous history of falciparum was found in 5, four had previous history of uncertain malaria and in three, no previous history of malaria was recorded. The liver was within normal size (≤140 mm) in 36 persons, and increased in size in 27 persons, of which enlarged (141–150 mm) in 14 and highly enlarged (beyond 150 mm) in 13 persons. Out of these 27 persons with enlarged livers 22 suffered from vivax previously. Altogether 18 out of 63 cases considered to be suffering from relapsed vivax cases in this study, which is alarming. Conclusions This simple, noninvasive procedure might provide a clue as to how relapse vivax cases can be determined.