BEVA primary care clinical guidelines: Equine parasite control

BACKGROUND

There is a lack of consensus on how best to balance our need to minimise the risk of parasite-associated disease in the individual horse, with the need to limit the use of anthelmintics in the population to preserve their efficacy through delaying further development of resistance.

OBJECTIVES

To develop evidence-based guidelines utilising a modified GRADE framework.

METHODS

A panel of veterinary scientists with relevant expertise and experience was convened. Relevant research questions were identified and developed with associated search terms being defined. Evidence in the veterinary literature was evaluated using the GRADE evidence-to-decision framework. Literature searches were performed utilising CAB abstracts and PubMed. Where there was insufficient evidence to answer the research question the panel developed practical guidance based on their collective knowledge and experience.

RESULTS

Search results are presented, and recommendation or practical guidance were made in response to 37 clinically relevant questions relating to the use of anthelmintics in horses.

MAIN LIMITATIONS

There was insufficient evidence to answer many of the questions with any degree of certainty and practical guidance frequently had to be based upon extrapolation of relevant information and the panel members' collective experience and opinions.

CONCLUSIONS

Equine parasite control practices and current recommendations have a weak evidence base. These guidelines highlight changes in equine parasite control that should be considered to reduce the threat of parasite-associated disease and delay the development of further anthelmintic resistance.

Prevalence of Blatticola blattae (Thelastomatidae) in German cockroaches Blattella germanica in Japan

A survey for nematode infection in German cockroaches captured in restaurants in various areas of Japan as well as the laboratory-bred colony was carried out. The nematodes were then identified morphologically and molecularly. Of the 320 German cockroaches collected at 79 restaurants in 26 prefectures in Japan, 66.6% (213/320) were found to be parasitized by a single species of pinworm in the hindgut. The mean number of pinworms per cockroach was less than 1.6. Of the three laboratory-bred lines of cockroaches examined, 2 lines (NIID and NK) were found to be infected with a single species of nematode. The prevalence was 93.0% (40/43) and 84.8% (39/46), respectively. The other laboratory line (WAT) was found to be free of the nematode infection. The nematode detected in this study was identified as Blatticola blattae. This is the first report of B. blattae infection in German cockroaches in Japan. Our study showed that B. blattae is distributed all over Japan together with its host Blattella germanica. An experimental infection with B. blattae in nematode-free cockroach by contaminating the rearing environment with infected-cockroach feces showed that once the environment of the cockroach is contaminated with B. blattae eggs, the pinworm infection could spread easily.

Enterobius Vermicularis: A Parasitic Cause of Appendicular Colic

Enterobius vermicularis is the most commonly identified parasite incidentally found within the appendix of a clinically diagnosed appendicitis. This parasitic cause of appendicular colic, primarily affecting children, is an important cause of negative appendicectomy. We report an unusual and interesting case of a young female who presented with clinical features of acute appendicitis. Laparoscopic appendicectomy revealed the presence of an Enterobius vermicularis infestation originating from the lumen of her vermiform appendix. Our case report is supplemented with a review of the literature, an overview of the parasitology, and discussion of pertinent symptomatology and peri-operative management strategies.

Confusing a Pollen Grain with a Parasite Egg: Infection or Traditional Medicine?

Camacho & Reinhard stated in the December 2019 issue of the KJP (57: 621–625) that we confused a pollen grain with an Enterobius egg found in the grave of a female adolescent residing in ancient Tehran 7,000 years ago. We want here to clarify and answer to the outlined points in their article.

Confusing a Pollen Grain with a Parasite Egg: an Appraisal of "Paleoparasitological Evidence of Pinworm (Enterobius Vermicularis) Infection in a Female Adolescent Residing in Ancient Tehran"

There is often the risk of confusing pollen grains with helminth eggs from archaeological sites. Thousands to millions of pollen grains can be recovered from archaeological burial sediments that represent past ritual, medication and environment. Some pollen grain types can be similar to parasite eggs. Such a confusion is represented by the diagnosis of enterobiasis in ancient Iran. The authors of this study confused a joint-pine (Ephedra spp.) pollen grain with a pinworm egg. This paper describes the specific Ephedra pollen morphology that can be confused with pinworm eggs.

Parasitic Infections

Parasitic infections of the gastrointestinal tract are a cause of morbidity to millions of individuals worldwide. These parasites are endemic in underdeveloped countries with poor sanitation allowing for spread through contaminated water supplies. While much is known about these parasites, the cutaneous manifestations caused by infection are infrequently reported in the literature. The deposition of the parasites into the perianal region often leads to significant skin irritation. Cutaneous findings vary from a mild pruritus ani to a macular rash to even severe perianal ulceration. This article discusses the perianal cutaneous findings caused by the parasitic illnesses, amebiasis, schistosomiasis, Enterobius vermicularis , strongyloidiasis, and cutaneous larva migrans, as well as their respective management.

Temporal and Spatial Distribution of Enterobius vermicularis (Nematoda: Oxyuridae) in the Prehistoric Americas

Investigations of Enterobius sp. infection in prehistory have produced a body of data that can be used to evaluate the geographic distribution of infection through time in the Americas. Regional variations in prevalence are evident. In North America, 119 pinworm positive samples were found in 1,112 samples from 28 sites with a prevalence of 10.7%. Almost all of the positive samples came from agricultural sites. From Brazil, 0 pinworm positive samples were found in 325 samples from 7 sites. For the Andes region, 22 pinworm positive samples were found in 411 samples from 26 sites for a prevalence of 5.3%. Detailed analyses of these data defined several trends. First, preagricultural sites less frequently show evidence of infection compared to agricultural populations. This is especially clear in the data from North America, but is also evident in the data from South America. Second, there is an apparent relationship between the commonality of pinworms in coprolites and the manner of constructing villages. These analyses show that ancient parasitism has substantial value in documenting the range of human behaviors that influence parasitic infections.

Treatment Options and Considerations for Intestinal Helminthic Infections

Objective: To review the literature regarding the epidemiology and treatment of intestinal helminthic infections. Data Sources: A literature search of MEDLINE (1946-January 2014), EMBASE (1980-January 2014), International Pharmaceutical Abstracts (1970-January 2014), and the Cochrane Library (1996-January 2014) was performed using the following terms: intestinal, helminthic, humans, United States, and individual drug names (albendazole, ivermectin, mebendazole, nitazoxanide, praziquantel, pyrantel pamoate). Secondary and tertiary references were obtained by reviewing related articles. Study Selection and Data Extraction: All English-language articles identified from the data sources and clinical studies using anthelmintic agents were included. Data Synthesis: The 2011 removal and continued absence of mebendazole from the market has left limited options for helminth infections. For hookworm, albendazole has a 72% cure rate compared to 32% for pyrantel pamoate. Albendazole, ivermectin, and nitazoxanide appear to be effective for Ascaris with cure rates of 88%, 100%, and 91%, respectively. Both albendazole and pyrantel pamoate have been evaluated for pinworm with cure rates of 94.1% and 96.3%, respectively. Combination therapy with ivermectin and albendazole produces cure rates of 38% to 80% for whipworm. For Strongyloides stercoralis, ivermectin cure rates are 93.1% to 96.8% compared with 63.3% for albendazole. Praziquantel is effective for intestinal trematode infections with cure rates of 97% to 100% while its efficacy against tapeworm ranges from 75% to 85%. Conclusions: Albendazole is the drug of choice for hookworm, Ascaris lumbricoides, and pinworm. In combination with ivermectin, it is the first-line agent for whipworm. Ivermectin is preferred for Strongyloides stercoralis, and praziquantel is effective against most nematodes and trematodes.

Prevalence of Enterobius vermicularis Infection among preschool children in kindergartens of Taipei City, Taiwan in 2008

The prevalence of Enterobius vermicularis infection among preschool children was reported to be low based on a 5-year screening program in Taipei City, Taiwan. The Taipei City government intended to terminate the E. vermicularis screening program among preschool children. Thus, we were entrusted with confirming whether pinworm infections among preschool children in Taipei City had truly declined. From each of 12 administrative districts 2-3 kindergartens were randomly selected for investigation. In total, 4,349 children were examined, of which 2,537 were boys and 1,812 were girls. The cellophane tape adhered to a glass slide was used, and all examinations were done by certified medical technologists. Results indicated that the overall prevalence rate of pinworm infections was 0.62% (27/4,349). Although the infection rate was higher among boys (0.67%, 17/2,537) than in girls (0.55%, 10/1,812), no significant difference was found (chi(2) = 0.399, P = 0.62). According to the administrative district, the infection rate ranged from no positive cases of E. vermicularis infection in the Xinyi, Zhongzhen, and Wanhua Districts (0%; 0/299, 0/165, and 0/358, respectively), to 0.26% (1/131) in Songshan District, with the highest rate of 1.88% (7/373) in Wenshan District. Because the overall infection rate (0.62%, 27/4,349) in the present study was unchanged compared to that (0.40%, 197/49,541) previously reported in 2005, we propose that regular pinworm screening and treatment programs should be continued in some parts of Taipei City.