Cellular immune response to SARS-CoV-2 and clinical presentation in individuals exposed to endemic malaria.

Ghana and other parts of West Africa have experienced lower COVID-19 mortality rates than other regions. This phenomenon has been hypothesized to be associated with previous exposure to infections such as malaria. This study investigated the immune response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the influence of previous malaria exposure.

Serological Evidence of Yersiniosis, Tick-Borne Encephalitis, West Nile, Hepatitis E, Crimean-Congo Hemorrhagic Fever, Lyme Borreliosis, and Brucellosis in Febrile Patients Presenting at Diverse Hospitals in Kenya.

Data on pathogen prevalence is crucial for informing exposure and disease risk. We evaluated serological evidence of tick-borne encephalitis (TBE), West Nile (WN), Hepatitis E virus (HEV), Crimean-Congo Hemorrhagic Fever (CCHF), Yersiniosis, Lyme Disease (LD), and brucellosis in 1033 patients presenting with acute febrile illness at 9 health care facilities from diverse ecological zones of Kenya: arid and semiarid (Garissa District Hospital, Lodwar District Hospital, Marigat District Hospital, Gilgil District Hospital), Lake Victoria basin (Kisumu District Hospital, Alupe District Hospital, Kombewa Sub-County Hospital), Kisii highland (Kisii District Hospital), and coastal (Malindi District Hospital). Epidemiological information of the patients such as geography, age, gender, and keeping animals were analyzed as potential risk factors.

Targeting remaining pockets of malaria transmission in Kenya to hasten progress towards national elimination goals: an assessment of prevalence and risk factors in children from the Lake endemic region.

Background: With an overall decline of malaria incidence, elimination of malaria is gradually becoming the next target for many of countries affected by the disease. In Kenya the national malaria control strategy is aiming to reach pre-elimination for most parts of the country. However, considerable heterogeneity in prevalence of the disease within the country and especially the remaining high prevalent region of the Lake endemic region is likely to slow progress towards this target.

Comparative evaluation of fluorescent in situ hybridization and Giemsa microscopy with quantitative real-time PCR technique in detecting malaria parasites in a holoendemic region of Kenya.

Background: Early and accurate diagnosis of malaria is important in treatment as well as in the clinical evaluation of drugs and vaccines. Evaluation of Giemsa-stained smears remains the gold standard for malaria diagnosis, although diagnostic errors and potential bias estimates of protective efficacy have been reported in practice. Plasmodium genus fluorescent in situ hybridization (P-Genus FISH) is a microscopy-based method that uses fluorescent labelled oligonucleotide probes targeted to pathogen specific ribosomal RNA fragments to detect malaria parasites in whole blood.

Direct detection of Leishmania from clinical samples.

The ability to rapidly and accurately diagnose leishmaniasis is a military priority. Testing was conducted to evaluate diagnostic sensitivity and specificity of field-expedient Leishmania genus and visceral Leishmania specific dual-fluorogenic, hydrolysis probe (TaqMan), polymerase chain reaction assays previously established for use in vector surveillance. Blood samples of patients with confirmed visceral leishmaniasis and controls without the disease from Baringo District, Kenya, were tested.

Frequency of Epstein - Barr Virus in Patients Presenting with Acute Febrile Illness in Kenya.

Background: Most acute febrile illnesses (AFI) are usually not associated with a specific diagnosis because of limitations of available diagnostics. This study reports on the frequency of EBV viremia and viral load in children and adults presenting with febrile illness in hospitals in Kenya.

Methodology/principal Findings: A pathogen surveillance study was conducted on patients presenting with AFI (N = 796) at outpatient departments in 8 hospitals located in diverse regions of Kenya.

Complement activation by merozoite antigens of Plasmodium falciparum.

Background: Complement (C) is a crucial part of the innate immune system and becomes over activated during malaria, resulting in depletion of C components, especially those for lectin pathway (LP), thereby compromising the host's innate defense. In this study, involvement of P. falciparum antigens in C activation was investigated.

How well do malaria tests correlate with disease severity? Comparison of parasite density in children with mild and severe malaria.

Background: Accurate diagnosis of malaria is key to proper management and control and an ideal diagnostic parameter that correlates to disease outcome is required. The former would be helpful in correctly identifying patients that need hospitalisation versus those that can be managed at home. This study determined how well the density estimates by microscopy, qPCR and HRP-2 correlate to malaria severity.

The seroprevalence and seroincidence of dengue virus infection in western Kenya.

Epidemics of dengue fever have been documented throughout the African continent over the past several decades, however little is known about the prevalence or incidence of dengue virus infection in the absence of an outbreak. No studies have analyzed the prevalence of dengue infection in western Kenya to date. This study describes the seroincidence and seroprevalence of dengue infection in western Kenya.

Development of a highly sensitive genus-specific quantitative reverse transcriptase real-time PCR assay for detection and quantitation of plasmodium by amplifying RNA and DNA of the 18S rRNA genes.

A highly sensitive genus-specific quantitative reverse transcriptase real-time PCR (qRT-PCR) assay for detection of Plasmodium has been developed. The assay amplifies total nucleic acids (RNA and DNA) of the 18S rRNA genes with a limit of detection of 0.002 parasite/μl using cultured synchronized ring stage 3D7 parasites.

Complement consumption in children with Plasmodium falciparum malaria.

Background: Complement (C) can be activated during malaria, C components consumed and inflammatory mediators produced. This has potential to impair host innate defence.

Methods: In a case-control study, C activation was assessed by measuring serum haemolytic activity (CH50), functional activity of each pathway and levels of C3a, C4a and C5a in children presenting at Kisumu District Hospital, western Kenya, with severe malarial anaemia (SMA) or uncomplicated malaria (UM).