Molecular characterization of G and P-types bovine rotavirus strains from Goiás, Brazil: high frequency of mixed P-type infections

In this study, 331 samples from calves less than one month old from a dairy herd in the district of Piracanjuba, state of Goiás, Brazil were tested for rotavirus. Thirty-three samples (9.9%) tested positive for rotavirus. Out of those, 31 were submitted to G and P characterization by reverse transcription followed by semi-nested polymerase chain reaction. Two samples were characterized as G6P[1], three as G10P[11] and five as G6P[11]. The majority of the samples (51.6%) displayed multiple P genotypes (P-genotype mixtures), including typical human genotypes P[4] and P[6M], suggesting the occurrence of co-infections and genetic reassortment. Also, the detection of human genotypes in bovine samples may be considered evidence of the zoonotic potential of rotaviruses. To our knowledge, this is the first report of such a high frequency of P genotype mixtures in bovine rotavirus samples. It also increases data on G and P rotavirus genotypes circulating in dairy herds in Brazil and can help in the development of more efficient immunization approaches, thereby controlling infection and reducing economical losses.

Leprosy frequency in the world, 1999-2010

In 1991, the World Health Organization (WHO) committed to reducing the prevalence of leprosy to below 1 in 10,000 inhabitants by 2000. Significant improvements in leprosy control have occurred, but leprosy remains a public health problem in many countries due to its high incidence and rate of transmission. This paper reviews data published by the WHO in the years 2000, 2005 and 2010. These data sets included 148 countries or territories that reported to the WHO at least once. Only four countries reported higher prevalence rates in 2010 than in 2000 and eight reported higher case detection rate (CDR) in 2009 than in 1999. Prevalence rate reductions were greater for the first five-year period examined, while CDR reductions were greater in the second five-year period. Thirty-six countries and territories reported at least one prevalence value higher than 1 per 10,000 inhabitants and 32 reported at least one CDR value higher than 9 per 100,000 inhabitants. A total of 39 countries fit at least one of these criteria and all were located in tropical regions.

Increased frequency of micronuclei in the lymphocytes of patients chronically infected with hepatitis B or hepatitis C virus

In this study, we analysed the frequency of micronuclei (MN), nucleoplasmic bridges (NPBs) and nuclear buds (NBUDs) and evaluated mutagen-induced sensitivity in the lymphocytes of patients chronically infected with hepatitis B virus (HBV) or hepatitis C virus (HCV). In total, 49 patients with chronic viral hepatitis (28 HBV-infected and 21 HCV-infected patients) and 33 healthy, non-infected blood donor controls were investigated. The frequencies (‰) of MN, NPBs and NBUDs in the controls were 4.41 ± 2.15, 1.15 ± 0.97 and 2.98 ± 1.31, respectively. The frequencies of MN and NPBs were significantly increased (p < 0.0001) in the patient group (7.01 ± 3.23 and 2.76 ± 2.08, respectively) compared with the control group. When considered separately, the HBV-infected patients (7.18 ± 3.57) and HCV-infected patients (3.27 ± 2.40) each had greater numbers of MN than did the controls (p < 0.0001). The HCV-infected patients displayed high numbers of NPBs (2.09 ± 1.33) and NBUDs (4.38 ± 3.28), but only the HBV-infected patients exhibited a significant difference (NPBs = 3.27 ± 2.40, p < 0.0001 and NBUDs = 4.71 ± 2.79, p = 0.03) in comparison with the controls. Similar results were obtained for males, but not for females, when all patients or the HBV-infected group was compared with the controls. The lymphocytes of the infected patients did not exhibit sensitivity to mutagen in comparison with the lymphocytes of the controls (p = 0.06). These results showed that the lymphocytes of patients who were chronically infected with HBV or HCV presented greater chromosomal instability.

Updating the geographical distribution and frequency of Aedes albopictus in Brazil with remarks regarding its range in the Americas

The geographical distribution of Aedes albopictus in Brazil was updated according to the data recorded across the country over the last eight years. Countrywide house indexes (HI) for Ae. albopictus in urban and suburban areas were described for the first time using a sample of Brazilian municipalities. This mosquito is currently present in at least 59% of the Brazilian municipalities and in 24 of the 27 federal units (i.e., 26 states and the Federal District). In 34 Brazilian municipalities, the HI values for Ae. albopictus were higher than those recorded for Ae. aegypti, reaching figures as high as HI = 7.72 in the Southeast Region. Remarks regarding the current range of this mosquito species in the Americas are also presented. Nineteen American countries are currently infested and few mainland American countries have not confirmed the occurrence of Ae. albopictus. The large distribution and high frequency of Ae. albopictus in the Americas may become a critical factor in the spread of arboviruses like chikungunya in the new world.

Frequency and molecular characterisation of Entamoeba histolytica, Entamoeba dispar, Entamoeba moshkovskii, and Entamoeba hartmanni in the context of water scarcity in northeastern Brazil

This study aimed to estimate the frequency, associated factors, and molecular characterisation of Entamoeba histolytica, Entamoeba dispar, Entamoeba moshkovskii, andEntamoeba hartmanni infections. We performed a survey (n = 213 subjects) to obtain parasitological, sanitation, and sociodemographic data. Faecal samples were processed through flotation and centrifugation methods.E. histolytica, E. dispar, E. moshkovskii, and E. hartmanni were identified by nested-polymerase chain reaction (PCR). The overall prevalence of infection was 22/213 (10.3%). The infection rate among subjects who drink rainwater collected from roofs in tanks was higher than the rate in subjects who drink desalinated water pumped from wells; similarly, the infection rate among subjects who practice open defecation was significantly higher than that of subjects with latrines. Out of the 22 samples positive for morphologically indistinguishableEntamoeba species, the differentiation by PCR was successful for 21. The species distribution was as follows: 57.1% to E. dispar, 23.8% to E. histolytica, 14.3% toE. histolytica and E. dispar, and 4.8% E. dispar and E. hartmanni. These data suggest a high prevalence of asymptomatic infection by the group of morphologically indistinguishable Entamoeba histolytica/dispar/moshkovskiicomplex and E. hartmanni species. In this context of water scarcity, the sanitary and socioenvironmental characteristics of the region appear to favour transmission.

Duration-frequency relationships of heavy rainfall in Santa Catarina, Brazil

The purpose of this study was to adjust equations that establish relationships between rainfall events with different duration and data from weather stations in the state of Santa Catarina, Brazil. In this study, the relationships between different duration heavy rainfalls from 13 weather stations of Santa Catarina were analyzed. From series of maximum annual rainfalls, and using the Gumbel-Chow distribution, the maximum rainfall for durations between 5 min and 24 h were estimated considering return periods from 2 to 100 years. The data fit to the Gumbel-Chow model was verified by the Kolmogorov-Smirnov test at 5 % significance. The coefficients of Bell's equation were adjusted to estimate the relationship between rainfall duration t (min) and the return period T (y) in relation to the maximum rainfall with a duration of 1 hour and a 10 year return period. Likewise, the coefficients of Bell's equation were adjusted based on the maximum rainfall with a duration of 1 day and a 10 year return period. The results showed that these relationships are viable to estimate short-duration rainfall events at locations where there are no rainfall records.

Feeding rate and frequency on juvenile pompano growth

The objective of this work was to evaluate the ideal feeding rate and frequency for juvenile pompano (Trachinotus marginatus). Two experiments were carried out in a completely randomized design, with three replicates each. In experiment I, 25 fish (4.8±0.6 g and 6.48±0.01 cm) were stocked in 15 tanks (50 L) during 21 days and fed 4, 8, 12, 16, and 20% body weight per day. In experiment II, 20 fish (4.1±0.1 g and 6.6±0.1 cm) were stocked in 15 tanks (40 L) during 28 days and fed 2, 6, 8, and 10 times a day. The tested feeding rates and frequencies did not influence survival. Final weight and length in experiment I were significantly lower in fish fed 4% body weight per day, whereas in experiment II only weight was significantly lower in fish fed 2 and 6 times a day. At the end of both experiments, apparent feed conversion showed significant difference, with the worst value observed for fish fed 20% body weight per day in experiment I and 2 times a day in experiment II. Juvenile pompano show better growth performance when fed 8% body weight per day and 8 times a day.