Changes in Anti-OV-16 IgG4 Responses to Onchocerciasis after Elimination of Transmission in the Central Endemic Zone of Guatemala.

Current WHO guidelines for onchocerciasis elimination provide requirements for stopping mass drug administration of ivermectin and the verification of elimination of transmission. These guidelines also recommend post-elimination surveillance (PES) based on entomological surveys. Serological markers in humans could complement entomological PES once the longevity of anti-OV-16 antibody responses is better understood.

Neuroinvasive Infection in a Ten-Year-Old Girl.

The nematode is an emerging human pathogen. Though its life cycle is not well studied, it likely infects humans after a bite from a black fly vector, which in turn acquires infective microfilariae from an infected canid. These microfilariae mature into an infective larval stage within the fly.

Onchocerciasis: Target product profiles of in vitro diagnostics to support onchocerciasis elimination mapping and mass drug administration stopping decisions.

In June 2021, the World Health Organization (WHO), recognizing the need for new diagnostics to support the control and elimination of onchocerciasis, published the target product profiles (TPPs) of new tests that would support the two most immediate needs: (a) mapping onchocerciasis in areas of low prevalence and (b) deciding when to stop mass drug administration programs. In both instances, the test should ideally detect an antigen specific for live, adult O. volvulus female worms.

Neglected Parasitic Infections: What Family Physicians Need to Know-A CDC Update.

Chagas disease, cysticercosis, and toxoplasmosis affect millions of people in the United States and are considered neglected parasitic diseases. Few resources are devoted to their surveillance, prevention, and treatment. Chagas disease, transmitted by kissing bugs, primarily affects people who have lived in Mexico, Central America, and South America, and it can cause heart disease and death if not treated.

A framework for scabies control.

Scabies is a neglected tropical disease (NTD) that causes a significant health burden, particularly in disadvantaged communities and where there is overcrowding. There is emerging evidence that ivermectin-based mass drug administration (MDA) can reduce the prevalence of scabies in some settings, but evidence remains limited, and there are no formal guidelines to inform control efforts. An informal World Health Organization (WHO) consultation was organized to find agreement on strategies for global control.

Scaling-Down Mass Ivermectin Treatment for Onchocerciasis Elimination: Modeling the Impact of the Geographical Unit for Decision Making.

Background: Due to spatial heterogeneity in onchocerciasis transmission, the duration of ivermectin mass drug administration (MDA) required for eliminating onchocerciasis will vary within endemic areas and the occurrence of transmission "hotspots" is inevitable. The geographical scale at which stop-MDA decisions are made will be a key driver in how rapidly national programs can scale down active intervention upon achieving the epidemiological targets for elimination.

Methods: We used 2 onchocerciasis models (EPIONCHO-IBM and ONCHOSIM) to predict the likelihood of achieving elimination by 2030 in Africa, accounting for variation in preintervention endemicity levels and histories of ivermectin treatment.

Coronavirus Disease 2019 (COVID-19) in Americans Aboard the Diamond Princess Cruise Ship.

Background: The Diamond Princess cruise ship was the site of a large outbreak of coronavirus disease 2019 (COVID-19). Of 437 Americans and their travel companions on the ship, 114 (26%) tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2).

Methods: We interviewed 229 American passengers and crew after disembarkation following a ship-based quarantine to identify risk factors for infection and characterize transmission onboard the ship.

Malaria and Parasitic Neglected Tropical Diseases: Potential Syndemics with COVID-19?

The COVID-19 pandemic, caused by SARS-CoV-2, have surpassed 5 million cases globally. Current models suggest that low- and middle-income countries (LMICs) will have a similar incidence but substantially lower mortality rate than high-income countries. However, malaria and neglected tropical diseases (NTDs) are prevalent in LMICs, and coinfections are likely.

The public health control of scabies: priorities for research and action.

Scabies is a parasitic disease of the skin that disproportionately affects disadvantaged populations. The disease causes considerable morbidity and leads to severe bacterial infection and immune-mediated disease. Scientific advances from the past 5 years suggest that scabies is amenable to population-level control, particularly through mass drug administration.

Evaluation of an OV-16 IgG4 Enzyme-Linked Immunosorbent Assay in Humans and Its Application to Determine the Dynamics of Antibody Responses in a Non-Human Primate Model of Infection.

Onchocerciasis is a neglected parasitic disease targeted for elimination. Current World Health Organization guidelines for elimination include monitoring antibody responses to the recombinant antigen OV-16 in children to demonstrate the absence of transmission. We report the performance characteristics of a modified OV-16 enzyme-linked immunosorbent assay (ELISA) and describe anti-OV-16 responses in serum samples from laboratory-inoculated nonhuman primates (NHPs) in relation to microfilariae (mf) in skin snip biopsies.

Comparison of PCR Methods for Detection in Skin Snip Biopsies from the Tshopo Province, Democratic Republic of the Congo.

Defining the optimal diagnostic tools for evaluating onchocerciasis elimination efforts in areas co-endemic for other filarial nematodes is imperative. This study compared three published polymerase chain reaction (PCR) methods: the -specific qPCR-O150, the pan-filarial qPCR melt curve analysis (MCA), and the O150-PCR enzyme-linked immunosorbent assay (ELISA) currently used for vector surveillance in skin snip biopsies (skin snips) collected from the Democratic Republic of the Congo. The pan-filarial qPCR-MCA was compared with species-specific qPCRs for and .

Refocusing vector assessment towards the elimination of onchocerciasis from Africa: a review of the current status in selected countries.

Measures to control onchocerciasis have been in place for well over 30 years. Recently, programs have turned from disease control towards transmission elimination. The absence of infective larvae in the black fly Simulium sp.

Onchocerciasis: shifting the target from control to elimination requires a new first-step-elimination mapping.

The meaning of 'mapping' in relation to onchocerciasis has changed at least three times over the past 50 years as the programmatic goals and the assessment tools have changed. With the current goal being global elimination of Onchocerca volvulus (OV), all areas where OV might currently be transmitted and where mass drug administration (MDA) with ivermectin treatment has not been delivered previously must now be identified by careful, detailed 'elimination mapping' as either OV endemic or not, so that appropriate programmatic targets can be established. New tools and strategies for such elimination mapping have become available, though ongoing studies must still be completed to define agreed upon optimal diagnostic evaluation units, sampling strategies and serologic tools.

Transitioning from river blindness control to elimination: steps toward stopping treatment.

The transition from onchocerciasis control to elimination requires country programmes to rethink their approach to a variety of activities as they move from addressing morbidity to addressing transmission of the parasite. Although the 2016 WHO guidelines provide extensive recommendations, it was beyond the scope of the document to provide guidance on all aspects of the transition. This paper will discuss some of the important issues that programmes are grappling with as they transition to elimination and provide some potential approaches that programmes can use to address them.

Diagnostics for onchocerciasis in the era of elimination.

In the past few years, efforts to eliminate onchocerciasis from Africa have intensified. These efforts are primarily based on the mass distribution of the anti-helminthic drug Mectizan™ (ivermectin). This program has led to the development of new guidelines by the World Health Organization for the verification that transmission has been suppressed and eventually eliminated.

Evaluation of Onchocerciasis Transmission in Tanzania: Preliminary Rapid Field Results in the Tukuyu Focus, 2015.

To compare diagnostic tests for onchocerciasis in a setting that has suppressed transmission, a randomized, age-stratified study was implemented in an area in Tanzania that had received 15 rounds of annual mass drug administration (MDA) with ivermectin. Study participants ( = 948) from 11 villages underwent a questionnaire, skin examination, skin snips, and blood draw. The burden of symptomatic disease was low.

Characterizing Reactivity to Antigens in Multiplex Bead Assays.

Multiplex bead assays (MBAs) may provide a powerful integrated tool for monitoring, evaluation, and post-elimination surveillance of onchocerciasis and co-endemic diseases; however, the specificity and sensitivity of antigens have not been characterized within this context. An MBA was developed to evaluate three antigens (OV-16, OV-17, and OV-33) for onchocerciasis. Receiver operating characteristics (ROC) analyses were used to characterize antigen performance using a panel of 610 specimens: 109 -positive specimens, 426 non-onchocerciasis controls with filarial and other confirmed parasitic infection, and 75 sera from patients with no other parasitic infection.

Survey of Obstetrician-Gynecologists in the United States About Taeniasis and Cysticercosis.

An estimated 50 million persons worldwide are infected with cysticerci, the larval forms of the Taenia solium tapeworm. Neurocysticercosis can cause seizures, epilepsy, and hydrocephalus, and fatal cases have been reported in the United States in immigrants and in travelers returning from endemic countries. Pregnant women with symptomatic neurocysticercosis present treatment challenges, whereas those with the adult tapeworm infection (i.

Notes from the Field: Splenomegaly of Unknown Etiology in Congolese Refugees Applying for Resettlement to the United States - Uganda, 2015.

Approximately 70,000-90,000 refugees are resettled to the United States each year, and during the next 5 years, 50,000 Congolese refugees are expected to arrive in the United States. The International Organization for Migration (IOM) performs refugee medical examinations overseas for the U.S.

Economic Analysis of the Impact of Overseas and Domestic Treatment and Screening Options for Intestinal Helminth Infection among US-Bound Refugees from Asia.

Background: Many U.S.-bound refugees travel from countries where intestinal parasites (hookworm, Trichuris trichuria, Ascaris lumbricoides, and Strongyloides stercoralis) are endemic.