Biodiversity of carbapenem-resistant bacteria in clinical samples from the Southwest Amazon region (Rondônia/Brazil)

Brazil is recognized for its biodiversity and the genetic variability of its organisms. This genetic variability becomes even more valuable when it is properly documented and accessible. Understanding bacterial diversity through molecular characterization is necessary as it can improve patient treatment, reduce the length of hospital stays and the selection of resistant bacteria, and generate data for health and epidemiological surveillance. In this sense, in this study, we aimed to understand the biodiversity and molecular epidemiology of carbapenem-resistant bacteria in clinical samples recovered in the state of Rondônia, located in the Southwest Amazon region. Retrospective data from the Central Public Health Laboratories (LACEN/RO) between 2018 and 2021 were analysed using the Laboratory Environment Manager Platform (GAL). Seventy-two species with carbapenem resistance profiles were identified, of which 25 species carried at least one gene encoding carbapenemases of classes A (blaKPC-like), B (blaNDM-like, blaSPM-like or blaVIM-like) and D (blaOXA-23-like, blaOXA-24-like, blaOXA-48-like, blaOXA-58-like or blaOXA-143-like), among which we will highlight Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii, Serratia marcescens, and Providencia spp. With these results, we hope to contribute to the field by providing epidemiological molecular data for state surveillance on bacterial resistance and assisting in public policy decision-making.

Attraction of the sandfly Lutzomyia longipalpis to possible biomarker compounds from dogs infected with Leishmania infantum

Lutzomyia longipalpis (Diptera: Psychodidae) is the primary vector of Leishmania infantum (Kinetoplastida: Trypanosomatidae) in the Americas. Studies have been carried out to identify new alternatives for monitoring and controlling this sandfly species, particularly with the use of chemical baits. The attractiveness of odours emitted by foxes and alcohols found in some plants has already been demonstrated in laboratory tests with Lu. longipalpis. However, no studies have evaluated the responses of these insects to volatile organic compounds (VOCs) emitted by dogs. The present study was carried out to investigate the effects on Lu. longipalpis of individual and blends of VOCs identified in hair from dogs infected with L. infantum. Effects in male and female Lu. longipalpis were assessed using wind tunnel methodology. Individual compounds including octanal, nonanal, decanal and heptadecane showed capacity for activating and/or attracting male Lu. longipalpis. Only decanal and nonanal showed effects on females. The combination of octanal, decanal and heptadecane increased activation and attraction behaviour in male sandflies, as did the blend of octanal and decanal. These findings indicate that VOCs emitted by dogs may be an interesting source of new attractants of sandflies.

Transferability of short tandem repeat markers for two wild Canid species inhabiting the Brazilian Cerrado

The maned wolf (Chrysocyon brachyurus) and the crab-eating fox (Cerdocyon thous) are two wild-canid species found in the Brazilian Cerrado. We tested cross-amplification and transferability of 29 short tandem repeat primers originally developed for cattle and domestic dogs and cats on 38 individuals of each of these two species, collected in the Emas National Park, which is the largest national park in the Cerrado region. Six of these primers were successfully transferred (CSSM-038, PEZ-05, PEZ-12, LOCO-13, LOCO-15, and PEZ-20); five of which were found to be polymorphic. Genetic parameter values (number of alleles per locus, observed and expected heterozygosities, and fixation indices) were within the expected range reported for canid populations worldwide.

A serological survey of arboviral diseases among the human population of the Andaman and Nicobar Islands, India

In an attempt to determine the prevalence of certain arthropod-borne viruses of public health importance amongst the human population of the Andaman and Nicobar Islands of India, 2,401 sera were collected from six major localities. The sera were analysed by the hemagglutination inhibition (HI) and neutralization (N) tests, using Chikungunya (CHIK), Japanese encephalitis (JE), West Nile (WN), dengue (DEN-2), Langat (TP-21) and Kyasanur Forest disease (KFD) viral antigens. The highest prevalence of HI antibodies was detected against KFD virus (22.4%), followed by Langat (20.2%), JE (5.9%), DEN-2 (3.1%), CHIK (2.9%) and WN (0.8%) viruses. Cross-reactions to the viral antigens were also noted. The results of N tests indicated a high prevalence of DEN-2 (25.4%) virus, followed by Langat (17.5%), CHIK (15.3%), KFD (12%), JE (2.19%) and WN (1.8%). These results are discussed in relation to important epidemiological parameters like age, sex and geographical location. To our knowledge, this is the first report of an extensive serosurvey of arthropod-borne viruses on these islands.

Soy protein isolate reduces the oxidizability of LDL and the generation of oxidized LDL autoantibodies in rabbits with diet-induced atherosclerosis

The incidence of atherosclerosis can be modified by diet, and plant-derived proteins have a beneficial effect, but the underlying mechanisms remain unclear. It has been suggested that oxidized LDL (oxLDL) and autoantibodies against oxLDL are important in the development of atherosclerosis. We analyzed these factors in rabbits fed a nonpurified diet supplemented with high cholesterol (10.0 g/kg) containing either 270.0 g/kg casein (CAS, n = 10) or 270.0 g/kg soy protein isolate (SPI, n = 10) for 2 mo. Plasma and purified serum LDL from rabbits were analyzed at d 0, 15, 30, 45 and 60 of treatment, and the size of atherosclerotic lesions was evaluated at d 60 of treatment. CAS-fed rabbits had significantly higher plasma cholesterol at d 15-45 and LDL cholesterol levels at d 15 and 30. Levels of trilinolein and phosphatidylcholine hydroperoxides were higher in the LDL fraction of rabbits fed CAS than in those fed SPI. Also, CAS-fed rabbits had higher levels of highly oxidized LDL [monoclonal antibody (mAb) 24-reactive oxLDL] in plasma at d 60, whereas SPI-fed rabbits had higher levels of minimally oxidized LDL (mAb 28-reactive oxLDL) at d 45. These results were consistent with the earlier formation of anti-oxLDL antibodies and the presence of a larger area of atherosclerotic lesion in rabbits fed the CAS diet. These data indicate the importance of both the type of dietary protein used in the induction of atherosclerosis and the relevance of immunologic mechanisms in addition to biochemical and physiologic factors in the pathogenesis of atherosclerosis.

Registered designation of origin areas of fermented food products defined by microbial phenotypes and artificial neural networks

Cheese produced from raw ewes' milk and chouriço, a Portuguese dry fermented sausage, are still produced in a traditional way in certain regions of Portugal by relying on colonization by microbial populations associated with the raw materials, equipment, and local environments. For the purpose of describing the product origins and types of these fermented foods, metabolic phenotypes can be used as descriptors of the product as well as to determine the presence of compounds with organoleptic value. The application of artificial neural networks to the metabolic profiles of bacterial isolates was assayed and allowed the separation of products from different regions. This method could then be used for the Registered Designation of Origin certification process of food products. Therefore, besides test panel results for these traditionally produced food products, another tool for validating products for the marketplace is available to the producers. The method can be improved for the detection of counterfeit products.

Dengue in Gujarat state, India during 1988 & 1989

Following the reports of epidemics of febrile illness from several rural and urban areas of Gujarat state (India) in 1988, epidemiological investigations were carried out and dengue (DEN) virus activity was demonstrated in large cities such as Surat and Rajkot as well as several villages in Sabarkantha district. Two strains of dengue type-2 each were isolated from human sera from Surat city and a village in Sabarkantha district. Six strains of dengue virus were isolated from Aedes aegypti mosquitoes collected at Chotasan village, two of which were confirmed as DEN type-2. Of the 560 patients' sera tested from different areas (including villages and townships), 122 showed evidence of dengue infection and another 236 showed a broader reaction with flaviviruses. Entomological investigations showed a widespread distribution of Ae. aegypti both in urban and rural areas. In the household conditions this mosquito was found to breed predominantly in containers with non-potable water. Amongst these, cement containers manufactured in towns and distributed to the villages seem to play an important role in the spread of this species. In non-residential areas prolific breeding of Ae. aegypti was observed in automobile tyre dumps, and varied types of scrap, in towns and villages. Distribution and relative prevalence of the species were studied in 46 towns and villages, covering the spectrum of rural-urban-continuum. These studies provide an indication regarding the mechanism of the spread of DEN virus through peoples' movement, transport, the process of urbanisation etc.

Serological response to Japanese encephalitis vaccine in a group of school children in South Arcot district of Tamil Nadu

A trial with Biken Japanese encephalitis (JE) vaccine made in Japan was carried out in South Arcot district of Tamil Nadu state, India. A total of 113 school children were included in the trial. The efficacy (as determined by serological response) and safety of the vaccine were evaluated. Side effects, though minor, were noted in 54.9 per cent of the children after each dose. The serum antibody titres were determined by mouse neutralization test, plaque reduction neutralization test and haemagglutination inhibition test. An antibody response to two-dose primary vaccination schedule was observed in 72.7 per cent, whereas 87.8 per cent of the vaccines responded positively after the booster dose administered one year after. Only about 20 per cent of the children had persisting antibodies one year after the primary vaccination. The results indicated a probable need of the third dose in the primary vaccination schedule.

Non A non B hepatitis epidemic in Rewa district of Madhya Pradesh

An epidemic of viral hepatitis occurred at Rewa district of Madhya Pradesh during December 1989 through April 1990. A total of 302 cases were admitted to Gandhi Memorial Hospital. Few cases were reported from the adjacent rural areas. Twenty six of the 40 wards of the city were affected and 7 wards were most affected with attack rates ranging from 3-7 per cent. Seventy one per cent of the hospitalised cases were 15 to 35 years of age. Males constituted 72.2% of the cases. In 37 patients (12.2%) the illness had a fatal outcome. The cases fatality rate was 7.9% in males and 20.6% in females. There were leakages in water supply pipe lines at many places which ran parallel to or were laid across open gutters. The source of infection appeared to be water contaminated by sewage. Results of serological tests indicated a non-A, non-B hepatitis viral aetiology of the epidemic.

Post-epidemic serological survey for JE virus antibodies in south Arcot district (Tamil Nadu)

Following an extensive epidemic of Japanese encephalitis (JE) in 1981, a serological survey was carried out in the South Arcot district of Tamil Nadu in April 1982. Serum specimens were obtained from 10 villages with serologically proven infections and 6 villages with no reported case of encephalitis during the 1981 epidemic. The serum specimens tested for haemagglutination inhibition, complement fixing and neutralizing antibodies, showed a high prevalence of JE (49.17%), West Nile (40.78%) and dengue (18.14%) viruses with predominance of JE. The prevalence did not differ between the villages with or without Japanese encephalities. There was also no difference between the family members and neighbours.

Clinical & virological study of dengue fever outbreak in Jalore city, Rajasthan 1985

An epidemic of acute febrile illness caused by dengue virus occurred in Jalore town, in south-west Rajasthan, in April and May, 1985. Most patients had classical signs and symptoms of dengue fever or had only a mild atypical febrile illness. A few patients had in addition haemorrhagic manifestations/shock or encephalitis. Virological studies (carried out by the National Institute of Virology, Pune) showed that dengue type 3 virus was the main etiological agent. This is the first reported outbreak of dengue in the arid zone in western Rajasthan, that occurred in summer (April-May) in contrast to other parts of India, where such outbreaks are commonly reported after the rains (between August and November).

Persistence of rabies antibody 5 years after pre-exposure prophylaxis with human diploid cell antirabies vaccine and antibody response to a single booster dose

In 1978, 22 staff members of the National Institute of Virology, Pune, India, were given two doses of human diploid cell antirabies vaccine (HDCV) for primary pre-exposure prophylactic immunization; the interval between the two doses being approximately 4 weeks. Eighteen of these 22 vaccinees were given a booster dose 1 year later. All 18 vaccinees developed protective levels of antibody; most of them had antibody levels exceeding 10 IU/ml. In 1984, 5 years after the booster dose, 11 (79.0%) of 14 vaccinees tested still possessed neutralizing antibody levels ranging from 0.5 IU/ml to 10 IU/ml. Fourteen days after the administration of a booster dose, the antibody levels ranged from 10 to greater than or equal to 100 IU/ml for all except one vaccine (5.2 IU/ml). These findings demonstrate that the majority of vaccines retained detectable neutralizing antibody after pre-exposure prophylaxis for as long as 5 years and that a single booster dose thereafter evoked a good antibody response.

Neutralizing antibody response to Japanese encephalitis inactivated mouse brain vaccine among laboratory personnel

Among vaccinees given two doses of JE Nakayama strain liquid vaccine, 41.8% had significant neutralizing (N) antibody response to the P20778 strain and 48.6% to the Japanese Nakayama strain. Among vaccinees who received three doses of the freeze-dried vaccine, the proportion of positive reactors was 53.8% when the sera were tested with the P20778 strain and 47.4% with the Nakayama strain. A fairly large proportion of those vaccinees who had responded positively to the latter vaccine were found to have lost detectable N antibodies to the P20778 strain and a smaller proportion to the Nakayama strain 13 to 17 months after the third dose of vaccine. Following the administration of a booster dose of the vaccine after this time interval, 65.2% and 56.5% of vaccinees responded positively to the P20778 strain and the Nakayama strain, respectively. The differences between the proportion of positive reactors to the two strains were not significant either for the liquid vaccine or the freeze-dried vaccine. An important finding was the priming effect of infection with West Nile (WN) virus before vaccination. Those vaccinees who had N antibody to WN virus before vaccination had a significantly higher N antibody response to the P20778 strain of JE virus than those who had no detectable antibody to WN virus. These findings indicate that the JE Nakayama strain vaccine would be efficacious in India, particularly in view of the widespread prevalence of WN virus infection.

Prevalence of antibodies to Japanese encephalitis and West Nile viruses among wild birds in the Krishna-Godavari Delta, Andhra Pradesh, India

In the Krishna-Godavari Delta region of the State of Andhra Pradesh, India, 866 sera obtained from trapped birds of 13 species were tested for neutralizing antibody to Japanese encephalitis (JE) virus; two species of birds belonging to the family Ardeidae, Ardeola grayii (pond heron) and Bubulcus ibis (cattle egret), contributed 514 of these sera. Neutralizing antibody to JE virus--i.e. sera giving positive reactions--was detected in 179 sera (34.8%) from these two species; in addition, two sera (0.4%) gave equivocal reactions, presumably indicating partial protection. There were only nine positive reactors (2.6%) among the remaining 352 sera from all other bird species. Of the 181 sera from ardeid birds in which neutralizing activity was detected, 174 were tested for neutralizing antibody to West Nile (WN) virus. The results indicated that 35.6% of these 179 sera had antibody specific to JE virus only and 63.8% possessed neutralizing antibodies to JE virus or to WN virus or to both; these figures represent 12.5% and 22.5% , respectively, of the total of 514 birds of these two species which were tested for neutralizing antibody to JE virus. The findings suggest that ardeid birds may be involved in the natural cycle of JE virus and, possibly, also of WN virus in India.

Etiology of the 1965 epidemic of febrile illness in Nagpur city, Maharashtra State, India

An investigation of an extensive outbreak of febrile illness during the months of April, May, and June 1965, in the city of Nagpur, Maharashtra State, showed that the main etiological agent was chikungunya virus. Dengue type 4 and Chandipura viruses were also active during this period. In all, 26 strains of virus were isolated from 60 acute phase human sera, and of these strains, 23 were identified as chikungunya virus, 2 as Chandipura, and 1 as dengue type 4. Five strains of chikungunya virus and 9 strains of dengue type 4 virus were isolated from 34 pools of Aedes aegypti collected from the affected areas. Results of complement fixation tests with acute-convalescent paired serum samples and single convalescent sera confirmed that chikungunya virus was the main etiological agent. The significance of these findings is discussed.