Extremely low malaria prevalence in a wetland specialist passerine

AbstractAvian malaria (caused by Plasmodium spp.) and avian malaria-like infections (caused by Haemoproteus spp.) are widespread and can seriously affect the health of their bird hosts, especially of immunologically naïve individuals. Therefore, these parasites have long been in the focus of bird-parasite studies. However, the species richness and diversity of these protozoan species have only been revealed since the use of molecular techniques. Diversity and prevalence of these parasites among different bird species and even between populations of a species show a large variation. Here, we investigated prevalence of avian malaria and avian malaria-like parasites in two distant populations of a non-migratory wetland specialist passerine, the bearded reedling (Panurus biarmicus). While previous studies have shown that reed-dwelling bird species often carry various blood parasite lineages and the presence of the vectors transmitting Plasmodium and Haemoproteus species has been confirmed from our study sites, prevalence of these parasites was extremely low in our populations. This may either suggest that bearded reedlings may avoid or quickly clear these infections, or these parasites cause high mortality in this species. The remarkably low prevalence of infection in this species is consistent with earlier studies and makes bearded reedlings a possible model organism for investigating the genetic or behavioural adaptations of parasite resistance.

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Incidence of avian malaria in hummingbirds in humid premontane forests of Pichincha Province, Ecuador: A pilot study

Veterinary World ◽

10.14202/vetworld.2021.889-896 ◽

2021 ◽

Vol 14 (4) ◽

pp. 889-896

Author(s):

Claudia S. Abad ◽

Markus P. Tellkamp ◽

Isidro R. Amaro ◽

Lilian M. Spencer

Keyword(s):

Avian Malaria ◽

Bird Species ◽

Predictor Variable ◽

Elevational Gradient ◽

Reproductive Rate ◽

Sex Bias ◽

Lower Elevation ◽

Blood Smears ◽

Avian Biodiversity ◽

Study Sites

Background and Aim: Avian malaria is a tropical disease caused by protozoans of the genera Plasmodium and Haemoproteus. As a nonlethal disease, avian malaria can affect the lifespan and reproductive rate of birds. If there is a differential effect depending on bird species, then this disease might have a significant effect on avian biodiversity. The current study aimed to determine the incidence of Plasmodium in hummingbirds in humid premontane forest areas. Materials and Methods: Blood samples (n=60) were collected from hummingbirds from two areas (Santuario de Aves Milpe and Hacienda Puyucunapi) of Pichincha Province, Ecuador. Prevalence and parasitemia were determined by microscopic examination of blood smears stained with Giemsa reagent. Both study sites are part of a 1000 m elevational gradient; hence, elevation was used as a predictor variable for prevalence and parasitemia levels in a Mann–Whitney U-test. This test was also used to test for a sex bias. Results: This study reports on a total of 12 bird species that inhabit both study sites. At Milpe, the lower elevation site, a prevalence of 100% was recorded, whereas at Puyucunapi, the prevalence was 96%. The combined prevalence was 97%. Elevation and sex did not influence prevalence nor parasitemia in hummingbirds. Conclusion: This study does not suggest a significant elevation or sex bias on prevalence and parasitemia in hummingbirds.

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Nest cameras do not affect nest survival in a meadow-nesting shorebird

Bird Conservation International ◽

10.1017/s0959270920000659 ◽

2020 ◽

pp. 1-10

Author(s):

VOLKER SALEWSKI ◽

LUIS SCHMIDT

Keyword(s):

Nest Survival ◽

Bird Species ◽

Conservation Strategies ◽

Survival Models ◽

Northern Germany ◽

Term Study ◽

Long Term Study ◽

Limosa Limosa ◽

Study Sites

Summary Identifying the fate of birds’ nests and the causes of breeding failure is often crucial for the development of conservation strategies for threatened species. However, collecting these data by repeatedly visiting nests might itself contribute to nest failure or bias. To solve this dilemma, automatic cameras have increasingly been used as a time-efficient means for nest monitoring. Here, we consider whether the use of cameras itself may influence hatching success of nests of the Black-tailed Godwit Limosa limosa at two long-term study sites in northern Germany. Annually between 2013 and 2019, cameras were used to monitor godwit nests. In 2014 and 2019, nests were randomly equipped with cameras or not, and nest survival checked independently of the cameras. Nest-survival models indicated that survival probabilities varied between years, sites and with time of the season, but were unaffected by the presence of cameras. Even though predation is the main cause of hatching failure in our study system, we conclude that predators did not learn to associate cameras with food either when the cameras were initially installed or after they had been used for several years. Cameras were thus an effective and non-deleterious tool to collect data for conservation in this case. As other bird species may react differently to cameras at their nests, and as other sets of predators may differ in their ability to associate cameras with food, the effect of cameras on breeding success should be carefully monitored when they are used in a new study system.

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The impact of HIV-associated immunosuppression on the Plasmodium falciparum chloroquine resistance transporter gene (PfCRT) of HIV patients in Akure, Nigeria

Bulletin of the National Research Centre ◽

10.1186/s42269-020-00401-0 ◽

2020 ◽

Vol 44 (1) ◽

Author(s):

Iyabo Adepeju Simon-Oke ◽

Adeola Olanireti Ade-Alao ◽

Foluso Ologundudu

Keyword(s):

Plasmodium Falciparum ◽

Malaria Prevalence ◽

Cd4 Count ◽

Chloroquine Resistance ◽

Hiv Care ◽

Transporter Gene ◽

Hiv Patients ◽

Chloroquine Resistance Transporter ◽

Hiv Test ◽

Low Prevalence

Abstract Background The study evaluated the prevalence of malaria and Plasmodium falciparum chloroquine resistance transporter gene (PfCRT) in HIV patients attending Specialist Hospital, Akure. This study was carried out between April and June 2019. Three hundred and seventeen (317) patients attending the antiretroviral clinic (ART) were involved, out of which 89 (28.08%) were males and 228 (71.92%) were females. HIV test was done using the Unigold® HIV test kit, malaria test was done using thick and thin blood smear, CD4 test was done using the Partec® CD4 counter and PCR was used to detect the presence of plasmodium falciparum mutant gene. The data obtained from this analysis was subjected to Pearson’s Chi-square test. Results The overall result showed low prevalence of malaria (23.03%) in the sampled patients. Highest malaria prevalence (31.0%) was recorded in HIV patients with CD4 count between 200–500 cells/μl of blood, with the males recording 24.7% malaria prevalence. The age group 20–29 years recorded the highest prevalence of 27.3%. A higher prevalence 91.1% of PfCRT gene in HIV-positive and (40.0%) in HIV-negative patients was recorded with 100% prevalence in patients with CD4 count ≤ 200. This shows that the low prevalence of malaria recorded in this study could be credited to good health-seeking attitude of HIV patients and the upscale of HIV care and treatment centres. Conclusion The high prevalence of PfCRT gene shows that treatment of malaria with chloroquine is still being practised despite the availability of artemisinin-based combination therapy (ACTs) as the recommended regimen for malaria treatment.

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Trichuris spp. in Animals, with Specific Reference to Neo-Tropical Rodents

Veterinary Sciences ◽

10.3390/vetsci8020015 ◽

2021 ◽

Vol 8 (2) ◽

pp. 15

Author(s):

Kegan Romelle Jones

Keyword(s):

Guinea Pig ◽

Guinea Pigs ◽

Clinical Signs ◽

Molecular Techniques ◽

Meat Production ◽

Specific Reference ◽

Hydrochoerus Hydrochaeris ◽

Present Information ◽

Low Prevalence ◽

A New Species

Trichuriasis is the clinical disease of animals infected with the parasite of the genus Trichuris. This review attempts to present information on Trichuris spp. infestation in neo-tropical rodents that are utilized for meat consumption by humans. Neo-tropical rodents utilized for meat production can be divided into two categories: those that have been domesticated, which include the guinea pig (Cavia porcellus), and those that are on the verge of domestication, such as the capybara (Hydrochoerus hydrochaeris), lappe (Cuniculus paca/Agouti paca), and agouti (Dasyprocta leporina). This document reviews the literature on the species of Trichuris that affects the rodents mentioned above, as well as the clinical signs observed. The literature obtained spans over sixty years, from 1951 to 2020. Trichuris spp. was found in these neo-tropical rodents mentioned. However, there is a dearth of information on the species of Trichuris that parasitize these animals. The capybara was the only rodent where some molecular techniques were used to identify a new species named T. cutillasae. In most cases, Trichuris spp. was found in combination with other endoparasites, and was found at a low prevalence in the lappe and guinea pig. The presence of Trichuris spp. ranged from 4.62–53.85% in the agouti, 4.21–10.00% in the lappe, 50% in the capybaras, and 1–31% in guinea pigs. Further work must be done towards molecular identification of various Trichuris spp. present in these rodents, as well as the clinical effect of infection on the performance of agouti, lappe, capybara, and guinea pigs.

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Clinical, virological and epidemiological characterization of dengue outbreak in Myanmar, 2015

Epidemiology and Infection ◽

10.1017/s0950268817000735 ◽

2017 ◽

Vol 145 (9) ◽

pp. 1886-1897 ◽

Cited By ~ 14

Author(s):

A. K. KYAW ◽

M. M. NGWE TUN ◽

M. L. MOI ◽

T. NABESHIMA ◽

K. T. SOE ◽

...

Keyword(s):

Primary Infection ◽

Phylogenetic Analyses ◽

Molecular Techniques ◽

Severe Dengue ◽

Envelope Gene ◽

Mosquito Vector ◽

Serum Samples ◽

Denv Serotypes ◽

Significant Difference ◽

Study Sites

SUMMARYHospital-based surveillance was conducted at two widely separated regions in Myanmar during the 2015 dengue epidemic. Acute phase serum samples were collected from 332 clinically diagnosed dengue patients during the peak season of dengue cases. Viremia levels were measured by quantitative real-time PCR and plaque assays using FcγRIIA-expressing and non-FcγRIIA-expressing BHK cells to specifically determine the infectious virus particles. By serology and molecular techniques, 280/332 (84·3%) were confirmed as dengue patients. All four serotypes of dengue virus (DENV) were isolated from among 104 laboratory-confirmed patients including two cases infected with two DENV serotypes. High percentage of primary infection was noted among the severe dengue patients. Patients with primary infection or DENV IgM negative demonstrated significantly higher viral loads but there was no significant difference among the severity groups. Viremia levels among dengue patients were notably high for a long period which was assumed to support the spread of the virus by the mosquito vector during epidemic. Phylogenetic analyses of the envelope gene of the epidemic strains revealed close similarity with the strains previously isolated in Myanmar and neighboring countries. DENV-1 dominated the epidemic in 2015 and the serotype (except DENV-3) and genotype distributions were similar in both study sites.

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Blood parasites in passerine birds from the Brazilian Atlantic Forest

Revista Brasileira de Parasitologia Veterinária ◽

10.1590/s1984-29612012000100003 ◽

2012 ◽

Vol 21 (1) ◽

pp. 7-15 ◽

Cited By ~ 15

Author(s):

Fabiane Sebaio ◽

Érika Martins Braga ◽

Felipe Branquinho ◽

Alan Fecchio ◽

Miguel Ângelo Marini

Keyword(s):

Atlantic Forest ◽

Bird Species ◽

Parasite Prevalence ◽

Neotropical Region ◽

Blood Parasite ◽

Blood Parasites ◽

Passerine Birds ◽

Blood Smears ◽

Temporal And Spatial ◽

Low Prevalence

Parasites may lead bird species to extinction, affect host temporal and spatial population dynamics, alter community structure and alter individuals’ social status. We evaluated blood parasite prevalence and intensity according to bird families and species, among 925 birds that were caught in 2000 and 2001, in the Atlantic Forest in the State of Minas Gerais, Brazil. We applied Giemsa staining to thin blood smears, to detect blood parasites. The birds (n = 15.8%) in 11 families, were infected by at least one parasite genus, especially Muscicapidae (28.3%) and Conopophagidae (25%). Among the 146 infected birds, Plasmodium was detected in all bird families and had the highest prevalence (54.8%). Trypanosoma, Haemoproteus and microfilaria had lower prevalence rates (23.3, 23.3 and 2.1%, respectively). Birds caught during the rainy season were more infected than birds caught during the dry season. The overall low prevalence of blood parasites in birds is similar to the patterns found elsewhere in the Neotropical region.

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Molecular breeding approaches for production of disease-resilient commercially important tobacco

Briefings in Functional Genomics ◽

10.1093/bfgp/elz038 ◽

2020 ◽

Vol 19 (1) ◽

pp. 10-25 ◽

Cited By ~ 1

Author(s):

Kaleem U Kakar ◽

Zarqa Nawaz ◽

Zhouqi Cui ◽

Nazeer Ahemd ◽

Xueliang Ren

Keyword(s):

Molecular Breeding ◽

Model Organism ◽

Resistance Breeding ◽

Underlying Disease ◽

Molecular Techniques ◽

Genetic Components ◽

Global Presence ◽

History Of ◽

Commercially Important ◽

Income Model

Abstract Tobacco is one of the most widely cultivated nonfood cash crops, a source of income, model organism for plant molecular research, a natural pesticide and of pharmaceutical importance. First domesticated in South Americas, the modern-day tobacco (Nicotiana tabacum) is now cultivated in more than 125 countries to generate revenues worth billions of dollars each year. However, the production of this crop is highly threatened by the global presence of devastating infectious agents, which cause huge fiscal loss. These threats have been battled through breeding for acquiring disease resilience in tobacco plants, first, via conventional and now with the use of modern molecular breeding approaches. For efficacy and precision, the characterization of the genetic components underlying disease resistance is the key tool in tobacco for resistance breeding programs. The past few decades have witnessed significant progress in resilience breeding through advanced molecular techniques. The current review discusses history of tobacco breeding since its time of origin till date, highlighting the most widely used techniques and recent advances in molecular research and strategies for resistance breeding. In addition, we narrate the budding possibilities for the future. This review will provide a comprehensive and valuable information for the tobacco growers and researchers to deal with the destructive infectious diseases.

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Malaria infection status of European Robins seems to associate with timing of autumn migration but not with actual condition

Parasitology ◽

10.1017/s0031182018002184 ◽

2019 ◽

Vol 146 (6) ◽

pp. 814-820

Author(s):

Nóra Ágh ◽

Imre Sándor Piross ◽

Gábor Majoros ◽

Tibor Csörgő ◽

Eszter Szöllősi

Keyword(s):

Avian Malaria ◽

Arrival Time ◽

Parasite Prevalence ◽

Malaria Prevalence ◽

Blood Parasites ◽

Autumn Migration ◽

Actual Condition ◽

Infection Status ◽

Stopover Site ◽

Age Related

AbstractAvian malaria parasites can negatively affect many aspects of the life of the passerines. Though these parasites may strongly affect the health and thus migration patterns of the birds also during autumn, previous studies on avian malaria focused mainly on the spring migration and the breeding periods of the birds. We investigated whether the prevalence of blood parasites varies in relation to biometrical traits, body condition and arrival time in the European Robin (Erithacus rubecula) during autumn migration. We found no sex or age related differences in avian malaria prevalence and no relationship between infection status and body size or actual condition of the birds was found either. However, the timing of autumn migration differed marginally between infected and non-infected juveniles, so that parasitized individuals arrived later at the Hungarian stopover site. This is either because avian malaria infections adversely affect the migration timing or migration speed of the birds, or because later arriving individuals come from more distant populations with possibly higher blood parasite prevalence. The possible delay that parasites cause in the arrival time of the birds during autumn migration could affect the whole migratory strategy and the breeding success of the birds in the next season.

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Power to Detect Trend in Short-Term Time Series of Bird Abundance

The Condor ◽

10.1093/condor/109.4.943 ◽

2007 ◽

Vol 109 (4) ◽

pp. 943-948

Author(s):

Wayne E. Thogmartin ◽

Brian R. Gray ◽

Maureen Gallagher ◽

Neal Young ◽

Jason J. Rohweder ◽

...

Keyword(s):

Sample Size ◽

Short Duration ◽

Bird Species ◽

Population Monitoring ◽

Short Term ◽

Wet Prairie ◽

Bird Abundance ◽

Point Counts ◽

Study Sites ◽

Species Specific

Abstract Avian point counts for population monitoring are often collected over a short timespan (e.g., 3–5 years). We examined whether power was adequate (power ≥0.80) in short-duration studies to warrant the calculation of trend estimates. We modeled power to detect trends in abundance indices of eight bird species occurring across three floodplain habitats (wet prairie, early successional forest, and mature forest) as a function of trend magnitude, sample size, and species-specific sampling and among-year variance components. Point counts (5 min) were collected from 365 locations distributed among 10 study sites along the lower Missouri River; counts were collected over the period 2002 to 2004. For all study species, power appeared adequate to detect trends in studies of short duration (three years) at a single site when exponential declines were relatively large in magnitude (more than −5% year−1) and the sample of point counts per year was ≥30. Efforts to monitor avian trends with point counts in small managed lands (i.e., refuges and parks) should recognize this sample size restriction by including point counts from offsite locations as a means of obtaining sufficient numbers of samples per strata. Trends of less than −5% year−1 are not likely to be consistently detected for most species over the short term, but short-term monitoring may still be useful as the basis for comparisons with future surveys.

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Head-to-Head Comparison of Two SARS-CoV-2 Serology Assays

The Journal of Applied Laboratory Medicine ◽

10.1093/jalm/jfaa125 ◽

2020 ◽

Vol 5 (6) ◽

pp. 1351-1357 ◽

Cited By ~ 4

Author(s):

Anna E Merrill ◽

J Brooks Jackson ◽

Alexandra Ehlers ◽

Dena Voss ◽

Matthew D Krasowski

Keyword(s):

Time Frame ◽

Cross Reactivity ◽

Molecular Techniques ◽

Respiratory Pathogens ◽

Serological Tests ◽

Antibody Assays ◽

Clinically Significant ◽

Low Prevalence ◽

Roche Diagnostics ◽

Unique Potential

Abstract Background While molecular techniques remain the gold standard for diagnosis of acute SARS-CoV-2 infection, serological tests have the unique potential to ascertain how much of the population has been exposed to the COVID-19 pathogen. There have been limited published studies to date documenting the performance of SARS-CoV-2 antibody assays. Methods We compared the DiaSorin Liaison SARS-CoV-2 S1/S2 IgG and Roche Diagnostics Elecsys Anti-SARS-CoV-2 assays using 228 samples spanning patients with positive PCR for SARS-CoV-2, patients with compatible symptoms but negative PCR, pre-COVID specimens, and potential cross-reactives. Results Both assays detected antibodies in 18/19 samples collected at least one week after a positive PCR result. Neither method consistently detected antibodies in specimens collected within one week of a positive PCR result (sensitivity < 50%), but antibodies were detected by only Roche in four samples in this time frame. Using 139 pre-COVID and 35 PCR-negative samples, the Roche and DiaSorin assays demonstrated specificities of 100.0% and 98.9%, respectively. Neither assay demonstrated cross-reactivity from other coronaviruses (229E, HKU1, NL63, OC43), respiratory pathogens (adenovirus, metapneumovirus, rhinovirus/enterovirus), or antibodies to other viruses (HIV, EBV, CMV, HBV, HCV, HAV). Discussion Overall, the qualitative interpretations afforded by the Roche and DiaSorin assays agreed for 97% of samples evaluated. Minor discrepancies in sensitivity and specificity were observed between methods, with the differences in specificity more clinically significant for our low-prevalence population. For the DiaSorin assay, all disagreements with the Roche assay occurred in samples with quantitative signals near the cut-off determining positivity.

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