Onchocerciasis Quiz

A chronic parasitic disease caused by the filarial worm, Onchocerca volvulus, transmitted through the bites of infected black flies of the genus Simulium.

The tiny larvae of the Onchocerca volvulus worm, which migrate through the skin and cause intense itching and skin problems.

Nodules of fibrous tissue that form under the skin, where adult Onchocerca volvulus worms live.

The genus of black flies that transmit Onchocerca volvulus through their bites.

The process by which the Onchocerca volvulus worm develops from larval stage to adult within the black fly.

A condition where the skin becomes discolored and resembles leopard skin due to Onchocerca volvulus infection.

The intense itching caused by the death of microfilariae in the skin.

The areas near rivers where the black flies that transmit Onchocerciasis are most common.

A group of roundworms, including Wuchereria bancrofti, Brugia malayi, and Brugia timori, that cause lymphatic filariasis.

The transmission of lymphatic filariasis occurs through the bite of an infected mosquito carrying L3 larvae.

The adult worms reside in the lymphatic vessels, while their offspring (microfilariae) circulate in the blood, primarily at night.

Lymphatic filariasis can manifest in various ways, including acute filarial fever, chronic lymphangitis (inflammation of lymph vessels), lymphadenitis (inflammation of lymph nodes), elephantiasis (swelling of body parts), and tropical pulmonary eosinophilia (TPE).

Culex mosquitoes transmit Wuchereria bancrofti, Mansonia mosquitoes transmit Brugia malayi and Brugia timori, and Simulium flies transmit Onchocerca volvulus (causing river blindness).

Age (peak between 20-30 years), sex (higher in men), migration, and immunity are factors influencing the risk of lymphatic filariasis. However, the specific immune mechanisms are not fully understood.

Urbanization, poverty, industrialization, illiteracy, and poor sanitation contribute to the spread of lymphatic filariasis. Suitable climate conditions for mosquito breeding (20-30°C temperature and 70% humidity) also play a crucial role.

The incubation period of lymphatic filariasis is not well-defined, but it is believed to be a few years.

The period between the initial infection with filarial larvae and the appearance of detectable microfilariae in the blood.

The time it takes for clinical symptoms of Lymphatic Filariasis to become evident.

The presence of adult filarial worms in the lymphatic system without any noticeable symptoms.

The presence of circulating microfilariae in the blood without any noticeable symptoms.

The first stage of Lymphatic Filariasis marked by acute episodes of inflammation in lymph vessels and nodes.

The final stage of Lymphatic Filariasis characterized by permanent damage to lymph vessels and the development of obstructive lesions.

A type of clinical manifestation of Lymphatic Filariasis that occurs when the adult worms cause blockage in the lymphatic vessels.

The presence of swelling in the scrotum caused by fluid build-up due to blocked lymphatic vessels.

A diagnostic test for onchocerciasis where a small piece of skin is removed and examined under a microscope.

A diagnostic test where diethylcarbamazine is applied to the skin and covered with a dressing. The presence of local dermatitis indicates a positive result.

The primary treatment for onchocerciasis, killing microfilariae and preventing transmission.

A drug that can be used alongside Ivermectin to reduce microfilarial loads and may have activity against adult worms.

A drug that kills adult worms but is rarely used due to side effects.

The primary goal of the Onchocerciasis Control Program (OCP) is to eliminate onchocerciasis as a public health problem and eliminate the parasite reservoir.

The Onchocerciasis Control Program (OCP) uses helicopters to aerially apply larvicide into the rivers and nearby breeding habitats of the fly.

Methods like using insecticides, wearing long sleeve shirts and pants, avoiding black fly habitats, and using insect nets to prevent getting bitten by the blackfly.

Infective larvae of the Onchocerca volvulus worm, which cause onchocerciasis, are transmitted to humans through the bite of infected female blackflies of the genus Simulium.

The microfilariae of Onchocerca volvulus can be found in the skin, blood, tears, sputum and urine.

Onchocerciasis, caused by Onchocerca volvulus infection, is a debilitating disease that can cause blindness and other serious health issues, but it is not fatal.

Adult female Onchocerca volvulus worms produce thousands of microfilariae per day.

The microfilariae of Onchocerca volvulus migrate to the subcutaneous tissue of the host, forming nodules where they mature into adult worms over a period of 6-12 months.

The microfilariae of Onchocerca volvulus are ingested by female black flies during a blood meal and develop into infective larvae within the fly.

Human are the only definitive host for the Onchocerca volvulus parasite.

The incubation period for onchocerciasis is usually a year or more after the infective bite.

A type of filariasis where the typical microfilariae (mf) are absent in the blood, despite the presence of infection. It's characterized by an exaggerated immune response to filarial antigens.

This condition presents with a combination of symptoms like paroxysmal cough, wheezing, low-grade fever, and sometimes blood in sputum. It's often accompanied by swollen lymph nodes and increased eosinophils in the blood.

Lymphoedema is a condition where fluid builds up in the tissues, causing swelling. It's classified into 7 stages, categorized by the presence or absence of swelling, skin folds, bumps, and other visual changes.

In this stage, swelling is present, but it disappears during the night. The skin remains smooth and there are no skin folds.

Swelling in this stage doesn't go away at night. The skin remains smooth, and there are still no skin folds.

Similar to Stage II, swelling persists at night. However, in this stage, shallow skin folds start to appear, and the skin stays otherwise smooth.

In Stage IV, swelling persists at night and shallow skin folds are present. The skin becomes bumpy, with nodules and irregularities.

The most common method for diagnosing filariasis is detecting microfilariae in the blood. This can be done by using thick blood smears, membrane filtration, or a special test called the DEC provocative test.