Molecular detection of drug-resistant Plasmodium falciparum mutants in Assam.

Background & objectives: The spread of drug-resistant Plasmodium falciparum (Pf) poses a serious threat to the control and elimination of malaria. The objective of this study was to detect the molecular biomarkers of antimalarial drug resistance in Pf in patients visiting a tertiary care hospital in Assam. Methods: Malaria was first detected in fever cases using microscopy and a rapid diagnostic test (RDT), and then confirmed using PCR. Pf chloroquine resistance transporter (Pfcrt), Pf multidrug resistance-1 (Pfmdr-1), and single-nucleotide polymorphisms linked to delayed parasite clearance after treatment with artemisinin MAL 10-688956 and MAL 13-1718319 and Kelch-13 propeller (PfK-13) genes were evaluated by PCR-restriction fragment length polymorphism (RFLP). Results: Sixty nine cases of malaria were found among 300 cases of fever. Of these, 54 were positive for Pf, 47 of which were confirmed by PCR. Pfcrt-K76T mutation was seen in 96.6 per cent and Pfmdr1-N86Y mutation in 84.2 per cent of cases. Mutation was not detected in MAL10 and MAL13 genes. Sequence analysis of Kelch-13 gene showed the presence of a novel mutation at amino acid position 675. Statistically, no significant association was found between the molecular biomarkers and demographic profile, clinical presentation and outcome of the cases. Interpretation & conclusions: Molecular surveillance is essential to assess the therapeutic efficacy of the drugs against circulating Pf isolates in Assam which are found to be highly resistant to CQ. The role of the new mutation found in the Kelch-13 gene in the development of artemisinin resistance in Assam needs to be thoroughly monitored in future research.

Serotyping of dengue viruses circulating during 2014-2015 in Assam, India.

Dengue has become endemic in India with outbreaks caused by all the four serotypes occurring almost every year. Dengue cases have been increasing alarmingly in Assam also. This study aimed to identify the dengue serotypes circulating in Assam. Clinically suspected dengue fever cases were included in the study. Viral RNA was extracted using QIAamp Viral RNA Mini Kit (Qiagen). Nested reverse transcriptase polymerase chain reaction was done for serotyping. The frequency of dengue was 25.23% with a peak during the period from September (22.56%) to October (26.22%). Two serotypes were detected, DEN-1 (72.7%) and DEN-2 (12.1%) and dual infection in 15.1%.

Molecular identification and detection of virulent factors in Helicobacter pylori from gastric biopsy samples of patients attended at Assam Medical College and Hospital, Dibrugarh, Assam, India.

The present study aimed to detect the major virulence determinants of Helicobacter pylori, the gastric bacteria by polymerase chain reaction from genomic DNA of 314 gastric biopsies from dyspeptic patients in 2015-2016 through upper gastrointestinal endoscopy. In 153 cases out of 314, the high prevalence of oipA gene followed by cagA-vacA s1 m1 combined genotypes was found in mostly gastritis/duodenitis patients followed by the peptic ulcer and normal patients. Therefore, the clinical significance of the virulence markers of H. pylori associated with the severe forms of gastroduodenal diseases is still a matter of controversy since the endoscopically normal patients were found to harbour the virulent genes.