based on the WHO Bench Aids for the diagnosis of intestinal parasites;
Tutor’s Guide: perform specific laboratory techniques; identify intestinal parasites by genus and species; quantify helminth eggs in faeces by Kato-Katz procedure.
the Lancet : Published Online July 31, 2015 http://dx.doi.org/10.1016/S0140-6736(15)61117-5
It is recommended that egg based quadrivalent vaccines for use in the 2019-2020 northern hemisphere influenza season contain the following:
an A/Brisbane/02/2018 (H1N1)pdm09-like virus;
an A(H3N2) virus to be announced on 21 March 2019*;
a B/Colorado/06/2017-like virus (B/Victoria/...2/87 lineage); and
a B/Phuket/3073/2013-like virus (B/Yamagata/16/88 lineage).
It is recommended that the influenza B virus component of trivalent vaccines for use in the 2019-2020 northern hemisphere influenza season be a B/Colorado/06/2017-like virus of the B/Victoria/2/87-lineage.
* In light of recent changes in the proportions of genetically and antigenically diverse A(H3N2) viruses, the recommendation for the A(H3N2) component has been postponed.
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Soil-transmitted helminths are a group of intestinal worms that include Ascaris lumbricoides (giant roundworm), Trichuris trichiura (whipworm), and Ancylostoma spp. (A. duodenale, A. ceylanicum) and Necator americanus (hookworms). Despite the clear biological differences among the different species,... their transmission is characterized by the same sequence of events: (i) infected individuals excrete worm eggs through their stool in soil; (ii) under optimal conditions of moisture and temperature the excreted eggs develop into infectious stages; and (iii) finally, infection occurs through oral uptake (Ascaris, Ancylostoma and Trichuris) or skin penetration (Ancylostoma and Necator) of these infectious stages (embryonated eggs and third stage larvae) that reside in the soil and/or in the environment (referring to their common name).
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Health ministries currently lack effective tools for monitoring and evaluation of schistosomiasis control programmes. Egg detection can be used, but the cost, challenges of obtaining samples, and the need for trained personnel and equipment limit the frequency of monitoring. The purpose of this TPP ...is to guide the development of new diagnostic tools to reliably measure when prevalence is above or below a cut-off of 10% in school-aged children. Communities remaining above 10% require annual MDA, while communities below 10% can reduce MDA frequency as long as < 10% prevalence can be maintained. However, the lack of a reliable test has hindered the development of maintenance strategies. The test is also needed to track changes of prevalence > 10% to ensure that annual MDA is reducing overall prevalence.
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HIV-1 infection disproportionately affects women in sub-Saharan Africa, where areas of high HIV-1 prevalence and Schistosoma haematobium endemicity largely overlap. Female genital schistosomiasis (FGS), caused most frequently by S. haematobium egg deposition in the genital tract, has been associated... with prevalent HIV-1 infection in cross-sectional studies. The presence of S. haematobium eggs in genital tissue is also associated with vascularization and the accumulation of CD4+ lymphocytes and macrophages, making the granuloma-associated environment a potential contributor to HIV-1 vulnerability. In addition to modulation of the local cervicovaginal environment, FGS has also been associated with a higher frequency of systemic CD4 T-cells expressing the chemokine receptor CCR5. Tissue-entrapped eggs are also associated with clinically visible FGS-associated manifestations in the cervicovaginal mucosa. FGS lesions may breach the intact cervicovaginal immune barrier and are hypothesized to provide an entry point for HIV-1 infection. However, the underlying mechanism for potential HIV-1 vulnerability in FGS has not been fully characterized and requires further investigation.
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Lesson on schistosomiasis (bilharziasis): Causes, Symptoms and Treatment. Schistosomiasis is caused by parasitic blood flukes from the genus schistosoma. Schistosoma cercariae penetrate human skin and enter the bloodstream of the infected individual, where the parasites enter the portal vein. Schist...osoma parasites also enter the mesenteric and bladder circulations, where they release eggs. Symptoms of schistosomiasis are related to the location of the parasites, the parasite burden and the amount of eggs produced. Systems affected in schistosomiasis include the hepatic, splenic, genitourinary, pulmonary, and nervous systems.
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DNA studies of Egyptian mummies shows evidence of the existence of Schistosomiasis about 5000 years ago. Schistosomiasis is increasing in prevalence, affecting nearly 10% of the world’s population and ranking second only to malaria as a cause of morbidity & mortality.
Schistosoma haematobium are... found in tropical Africa & part of southwest Asia.
Schistosoma mansoni are found in tropical Africa, part of southwest Asia, south America & Caribbean islands.
Schistosoma japonicum are found in parts of Japan, China, Philippines, India & part of southeast Asia.
Blood flukes are known as schistosomes because of the "split body" on the ventral side of the male, in which the female is held during insemination and egg laying.
Man is the definite host harbouring adult parasites, and fresh water snails are intermediate hosts.
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People who accidentally swallow the eggs of the Echinococcus granulosus tapeworm are at risk for infection. Dogs that eat home-slaughtered sheep and other livestock become infected with the tapeworm Echinococcus granulosus and the tapeworm eggs can be found in their stool. Direct contact with infect...ed dogs, particularly intimate contact between children and their pet dogs, may lead to human infection. Ingestion of soil, water and vegetables contaminated with infected dog feces may also lead to infections. Echinococcus granulosus eggs can survive snow and freezing conditions.
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A dermatologist can often diagnose scabies by visually examining a patient’s skin from head to toe.
To make sure that a patient has scabies, a dermatologist may remove some skin. This is painless. Your dermatologist will put the skin on a glass slide and look at the slide under a microscope. If y...our dermatologist sees scabies mites or their eggs, it is certain that you have scabies.
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Scabies is caused by Sarcoptes scabiei, a mite which lays its eggs under the surface of your skin and reproduces. When the eggs hatch, mites crawl out onto your skin and make new burrows.
The mites can be difficult to identify and may be confused with pubic lice as both conditions cause itching in ...the genital area.
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Human scabies is caused by an infestation of the skin by the human itch mite (Sarcoptes scabiei var. hominis). The microscopic scabies mite burrows into the upper layer of the skin where it lives and lays its eggs.
Scabies is found worldwide and affects people of all races and social classes. Scabi...es can spread rapidly under crowded conditions where close body and skin contact is frequent. Institutions such as nursing homes, extended-care facilities and prisons are often sites of scabies outbreaks. Child care facilities also are a common site of scabies infestations.
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Human scabies is a parasitic infestation caused by Sarcoptes scabiei var hominis. The microscopic mite burrows into the skin and lays eggs, eventually triggering a host immune response that leads to intense itching and rash. Scabies infestation may be complicated by bacterial infection, leading to t...he development of skin sores that, in turn, may lead to the development of more serious consequences such as septicaemia, heart disease and chronic kidney disease. In 2017, scabies and other ectoparasites were included as Neglected Tropical Diseases (NTDs), in response to requests from Member States and the recommendations of the WHO Strategic and Technical Advisory Group for NTDs.
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Scabies is an infestation of the skin by the human itch mite (Sarcoptes scabiei var. hominis). The microscopic scabies mite burrows into the upper layer of the skin where it lives and lays its eggs. The most common symptoms of scabies are intense itching and a pimple-like skin rash. The scabies mite... usually is spread by direct, prolonged, skin-to-skin contact with a person who has scabies.
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Taenia saginata is a zoonotic tapeworm that is of economic importance in countries where cattle are kept. The parasite is transmitted from human tapeworm carriers (taeniosis) to bovines (cysticercosis) by excretion of eggs or proglottids containing eggs into the environment via the stool. Bovines ca...n then ingest the eggs through contaminated feed or water. After ingestion, the eggs hatch and release oncospheres in the small intestines, where the oncospheres penetrate the intestinal wall to reach the blood circulation. This distributes them throughout the body, but primarily to muscle tissue, where they develop into cysticerci. For humans to become infected with T. saginata, raw or undercooked bovine meat or offal containing infective cysts must be consumed. Bovine cysticercosis has been associated with various environmental factors related to water sources, such as animals having access to surface water, flooding of pastures and proximity to wastewater sources.
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WHO strongly recommends discontinuation of the nerve tissue vaccine, and replacement with modern concentrated and purified cell culture derived vaccines (CCDV) and embryonated eggbased rabies vaccines.
These vaccines must comply with WHO criteria for potency and innocuity following satisfactory ass...essment in humans during well-designed field trials
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oil-transmitted helminth (STH) infections are among the most common infections worldwide and affect the poorest and most deprived communities.
They are transmitted by eggs present in human faeces which in turn contaminate soil in areas where sanitation is poor.
The main species that infect peopl...e are the roundworm (Ascaris lumbricoides), the whipworm (Trichuris trichiura) and the hookworms (Necator americanus and Ancylostoma duodenale).
Intestinal worms produce a wide range of symptoms including intestinal manifestations (diarrhoea, abdominal pain), general malaise and weakness. Hookworms cause chronic intestinal blood loss that result in anaemia.
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Soil-transmitted helminth (STH) infections are among the most common infections worldwide and affect the poorest and most deprived communities. They are transmitted by eggs present in human faeces which in turn contaminate soil in areas where sanitation is poor.
Schistosomiasis and soil-transmitted helminths (STH) infections are major public health problems. We aimed to study the 6-mo impact of mass drug administration with praziquantel and albendazole on urinary schistosomiasis and STH.We examined children (aged 2–15 y) from one hamlet, who provided urin...e and faeces samples at baseline (n=197), 1 mo (n=102) and 6 mo (n=92); 67 completed the protocol.At baseline, 47/67 (70.1%) children presented Schistosoma haematobium (75.8% in the baseline total sample) and 12/67 (17.9%) with STH (30.5% in the initial sample, p=0.010). Among the children, 47.3% had heavy Schistosoma haematobium infection. The most frequent STH was Trichuris trichiura in 9.0%. We also found Hymenolepis nana (13.2%) and Plasmodium falciparum (9.1%) infections and anaemia (82.1%). One mo after chemotherapy there was a significant (p=0.013) reduction of Schistosoma haematobium prevalence (23.5%) and a high egg reduction rate (86.9%). Considering the sample of 67 children, the mean egg concentration was 498 at baseline, 65 at 1 mo and 252 at 6 mo (p<0.05). We also observed a reduction in STH infections, 50% in Ascaris lumbricoides, 33.3% in T. trichiura and 50% in hookworms. At 6 mo, the prevalence of Schistosoma haematobium (76.1%) was similar to the baseline and the STH reduction was not significant.Longitudinal studies have reported many losses in these settings, but we were able to show that mass drug administration for control of schistosomiasis and STH present low effectiveness, that reinfections occur rapidly and that stand alone anthelmintic therapy is not a sustainable choice.
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