Epidemiological evaluation of patients submitted to the galactomannan test with suspected invasive aspergillosis

Invasive aspergillosis (IA) increases dramatically when there is potential risk in many patient groups, in particular with hematological malignancies. The purpose of the study was to trace the epidemiological profile of patients who underwent galactomannan test by ELISA with suspected IA and to determine the factors that contribute to the development of the disease. We evaluated 264 patients who underwent galactomannan test with suspected IA from 2013 to 2015.The clinical-epidemiological characteristics were determined using descriptive statistics. The variables were evaluated using the chi-square test (χ2) and the G-test, with p-value considered significant below 0.05. According to the classification for IA by the European Organization for Research and Treatment of Cancer, the disease was considered proven in 7.3%, defined by positive culture for the fungus, 6.4% as probable through detection of galactomannan and the presence of pulmonary infiltrates and 5.1% as possible by radiological alterations suggestive of IA and negative galactomannan test. The mortality rate was 31.6% of all patients and 61.3% for proven / probable / possible IA indicating that the disease was significantly associated with the risk of death. According to these result indications and considering the high mortality rate caused by the development of IA, as well as the fact that early therapy promotes significant improvement in the patients’ prognosis, we conclude that the detection of galactomannan may be considered an effective method to aid the identification of IA. KEY WORDS: Invasive pulmonary aspergillosis; neutropenia; enzyme-liked immunosorbent assay; ELISA test searching for Aspergillus; galactomannan.

High prevalence and intensity of fish nematodes with zoonotic potential in the Brazilian Amazon, including a brief reflection on the absence of human infections

This study aimed to characterize the prevalence, mean abundance, and mean intensity of potential fish-borne zoonotic nematode larvae infecting the predator fish Hoplias aff. malabaricus from the Tapajós River, in the municipality of Santarém, in the Brazilian Amazon. After capture, the specimens of H. aff. malabaricus were analyzed for infection by Contracaecum sp. and Eustrongylides sp. third-stage larvae, and the prevalence, mean abundance, and mean intensity were calculated. A literature search was carried out to clarify the relationship between these indicators and eventual human cases of infection in the Amazon region. Third-stage larvae of nematodes of the Contracaecum and Eustrongylides genera were found in the specimens of H. aff. malabaricus sampled from the Tapajós River. The prevalence of Contracaecum larvae was 100%, while its mean abundance and mean intensity were both 54.8 larvae/fish. The prevalence of Eustrongylides larvae was 62.9%, and its mean abundance and mean intensity were 1.8 and 2.8 larvae/fish, respectively. Despite the high prevalence and intensity values, there are no cases of human infection by these nematode larvae in the Brazilian Amazon reported. The absence of human infections by these nematode larvae in the Brazilian Amazon despite the high prevalence/intensity of Contracaecum and Eustrongylides larvae and the high consumption of fish in the region, is most probably due to the fact that the local populations do not eat raw or undercooked fish. However, it is noteworthy that the absence of zoonotic cases in the region is based only on the examination of the available published papers. A better knowledge of the situation would require surveying hospitals and clinics, and data from the region’s medical treatment facilities. However, the authors consider that cases of human infection, if any, are extremely rare, mainly due to the eating habits of the local population. KEY WORDS: Amazon basin; freshwater fish; public health; parasitic infection; zoonosis.

The ecology of herd immunity

The COVID-19 pandemic that began in early 2020 is currently the subject of thousands of articles on the various aspects of its epidemiology. One recurrent theme is the phenomenon of herd immunity or herd effect. In this article, I present a short history of the concept, the arguments around its nomenclature, and the ecologist’s view of the herd effect, using the case history of the sleeping sickness control in Africa. KEY WORDS: Herd immunity; convergence; ecology; sleeping sickness.

Enteric parasites and socio-epidemiological variables in an academic community

Studies linking human health to environmental conditions are essential since parasitic diseases are connected to environmental and sanitary aspects. This study identified the prevalence of enteric parasites in an academic community in the municipality of Santo Antônio de Jesus, Bahia, Brazil. The purpose was to determine the existence, or not, of links between infections and socio-epidemiological variables, such as personal hygiene habits, the presence of sewage systems and the environment. Participants answered a questionnaire and received universal collectors for fecal samples. Spontaneous sedimentation methods and Rugai were used for diagnosis. One hundred twenty-one samples were analyzed, in which a 38.8% parasite prevalence was detected as well as a 61.7% rate of monoparasitism, as well as a predominance of protozoa Endolimax nana (78.7%) and Giardia duodenalis (21.3%). Among parasitized individuals, 97.9% lived in the Recôncavo Baiano region. The following statistical significance stands out in the findings, with p<0.05: individuals who had already bathed in the local river were more likely to be parasitized than those who had not (p = 0.034) and individuals who washed their hands more frequently before meals proved to be less prone to intestinal parasitic infections (p = 0.018). Results evidenced the presence of enteric parasites in a number of participants in spite of their being university students. The socio-epidemiological variables analyzed brought to light characteristics that favor the establishment of the epidemiological infection triad, such as improper packaging of household waste on disposal and no records of regular domestic water tank cleaning. KEY WORDS: Enteric parasites; environment; diagnosis; health education.

Myasthenia gravis and COVID-19: a systematic review of case reports and case series

Myasthenia gravis (MG) is an autoimmune disease involving neuromuscular transmission and possible respiratory failure when concomitant with COVID-19. The aim of this study was to analyze the need for ventilatory support (VS), length of hospital stay (LOS) and mortality in patients diagnosed with MG and COVID-19. In this systematic review, PubMed, SciELO, LILACS, MEDLINE and IBECS databases were searched for primary studies published from January 2010 to March 2021, with no language restrictions. Fourteen eligible studies were identified. The main factor associated with the need for VS was the use of antibiotics other than azithromycin (AZM) for the treatment of COVID-19 (RR 1.60; 95% CI 1.20–2.91; p = 0.009). Patients who used hydroxychloroquine (HCQ) and AZM had almost twice the risk of needing invasive ventilatory support (IVS) (RR 1.94; 95% CI 1.07-3.52; p = 0.16). There were nonsignificant trends towards less need for IVS in patients who used intravenous immunoglobulin (IVIg) and corticosteroid therapy (RR 0.54; 95% CI 0.09–3.26; p = 0.60). There was a trend towards shorter LOS in patients who received therapy with IVIg and corticosteroid therapy [8 (5 - 8) vs 19 (12.2–23.7); p = 0.007]. 10.3% (n = 4/39) died and 100% did not use IVIg or IVIg and prednisone. There was a non-significant trend towards higher mortality in patients who used AZM (RR 2.55; 95% CI 0.26–30.02; p = 0.60). IVIg and corticotherapy presented themselves as a favorable alternative in relation to the outcomes.KEY WORDS: Coronavirus infections; length of stay; Myasthenia gravis; Respiratory insufficiency.

TRYPANOSOMA spp. in captive primates in a brazilian zoo

Captive animals, despite the constant care provided, are susceptible to infections from different sources. We herein report the natural trypanosome infection of 11 (28.2% positive) out of 39 non-human primates from 13 different species, in a Brazilian zoological park. Immunofluorescent antibody test (IFAT) and conventional polymerase chain reaction (cPCR) ruled out Trypanosoma cruzi, the etiological agent of Chagas disease. However, sequencing performed with positive samples employing hsp70 primers revealed similarities from 86% to 88% to diverse trypanosomes, including T. cruzi, Trypanosoma grayi, Trypanosoma lewisi, Trypanosoma rangeli and Trypanosoma vivax. We believe that the low similarity values obtained by sequencing reflect the difficulties in the molecular identification of trypanosomes, which share a large portion of their genetic material; this similarity may also preclude the diagnosis of co-infection by more than one trypanosome species. Thus, our study demonstrates the presence of diverse trypanosomes in primates, which are susceptible to infection by these parasites. Mechanical devices such as windows and bed nets, etc., are required to avoid vector insects in these environments, in addition to preventive quarantining of animals recently introduced into zoos. Therefore, investigation of the parasites in both the animals already residing in the zoo and those being introduced is of paramount importance, although no easy task. KEY WORDS: Non-human primates; monkey; diagnosis; trypanosomes.

Infection rate by TOXOPLASMA GONDII in free-range and broiler chickens in the states of Rio Grande do Norte and Paraíba, Brazil

Toxoplasmosis is a zoonosis caused by Toxoplasma gondii, a protozoan that has a cosmopolitan geographic distribution and low specificity for intermediate hosts. Domestic chickens are among the most important hosts in toxoplasmosis epidemiology, since they are potential sources of infection for humans, in addition to indicating environmental contamination by protozoa. In this work, we studied the prevalence of T. gondii infection in chickens in different breeding systems from distinct mesoregions of Rio Grande do Norte and Paraiba States: broiler chickens from commercial farms and free-range chickens from small farms. Indirect fluorescent antibody test (IFAT) and ELISA techniques were used for detecting specific antibodies in blood samples from the birds. There were no seropositive samples among the broilers tested, indicating that intensive management limited the chances of infection for these animals. Amongthe free-range chickens, the frequency of IgG anti-T. gondii detected by IFAT and ELISA were 37.9% and 40.4% respectively. Among the seropositive samples by IFAT, 33 (27.1%) were positive at a dilution of 1:16; in 1:32, 31 (25.4%); in 1:64, 24 (19.7%); 15 (12.3%) in 1:128, and 19 presented titers greater than or equal to 1:256 (15.6%). The substantial concordance observed between IFAT and ELISA signifies these methods are effective methodologies for the diagnosis of avian toxoplasmosis. The high prevalence of specific antibodies among poultry in the studied region highlights the potential risk of T. gondii transmission to humans through consumption of infected meat.KEY WORDS: Toxoplasma gondii; chicken infection; toxoplasmosis transmission; seroprevalence.

Soil contamination by zoonotic parasites in leisure areas: an integrative review

Enteropasites are a risk to both human and animal health, and soil is an important route for their propagation and perpetuation, due to the easy animal access to leisure environments. Furthermore, the contamination of these areas is a public health problem, due to the high number of people who visit these places and can acquire these parasitoses. The purpose of this study was to research information described in the scientific literature on the prevalenceof parasites with zoonotic potential in leisure areas, their distribution and associated factors. This is an integrative review of the literature in which scientific studies on parasites of zoonotic potential in leisure areas were selected from the Virtual Health Library, with MEDLINE and LILACS as its database, in addition to PUBMED, SCIELO and “Periódicos Capes” published between 2010 and 2020 in Portuguese, English and Spanish. Eleven articles were selectedfrom the 494 found after applying criteria for inclusion, exclusion and content evaluation. Ancylostoma spp. and Toxocara spp. proved to be widely distributed, and soil contamination by parasites is directly linked to the presence of animals in these environments, due to their feces and favorable environmental conditions.KEY WORDS: intestinal parasites; zoonoses; environmental contamination; public health.

Awareness and understanding of risk factors for intestinal parasitic infections at a public university in southern Brazil

Intestinal parasitoses are highly prevalent in underdeveloped countries such as Brazil. These infirmities may be analyzed looking at the epidemiological triad of the diseases, which consists of host health, the parasite itself and the environment in question. This study aimed to identify the presence of predisposing factors for contamination by enteroparasites in the students of a public university in the South of Brazil. A transversal and descriptive study was carried out with qualitative and quantitative components, and data prospection by means of a questionnaire answered by the students. Only 63.9% of the subjects wash their hands before meals. However, the most alarming factor observed was the environmental instance as the university restroomsare often unclean, which was reported in 99.0% of the questionnaires.KEY WORDS: Intestinal parasites; undergraduate students; health-education

Effects of multiple doses of simvastatin and artesunate monotherapy on SCHISTOSOMA MANSONI adult worms during infection in hyperlidemic mice

A single dose of simvastatin and of artesunate monotherapy cause damage to the reproductive system of schistosomes as well as severe tegumental damage in male worms recovered from mice fed high-fat chow. This study aims to investigate whether treatment with multipledose regimes may offer more antischistosomal activity advantages than single daily dosing in mice fed high-fat chow. For this purpose, nine weeks post-infection, Swiss Webster mice were gavaged with simvastatin (200 mg/kg) or artesunate (300 mg/kg) for five consecutive days and euthanized two weeks post-treatment. Adult worms were analyzed using brightfieldmicroscopy, confocal microscopy and scanning electron microscopy, presenting damages caused by simvastatin and artesunate to the reproductive system of males and females as well as tegument alterations, including peeling, sloughing areas, loss of tubercles, tegumental bubbles and tegument rupture exposing subtegumental tissue. The overall findings in this study revealed the potential antischistosomal activity of simvastatin and artesunate against Schistosoma mansoni adult worms, in addition to showing that multiple doses of either monotherapy caused severe damage to the tegument.KEY WORDS: Schistosoma mansoni; hyperlipidemia; simvastatin; artesunate; microscopy.