Review of clinical aspects, epidemiology and diagnosis of haemotropic Mycoplasma ovis in small ruminants: current status and future perspectives in tropics focusing on Malaysia

Abstract

Mycoplasma ovis (formerly Eperythrozoon ovis ) is an epierythrocytic parasitic bacterium of small ruminants known as haemotropic mycoplasma, which is transmitted mechanically by biting flies and contaminated instruments. Acute mycoplasmosis causes severe haemolytic anaemia and mortality in young animals. At the same time, chronic disease may produce mild anaemia and varying degrees of morbidity depending on several factors, including age, reproductive status, the plane of nutrition, immunological status and the presence of concurrent infection. Haemotropic Mycoplasma ovis is currently recognised as an emerging zoonotic pathogen which is widely distributed in the sheep and goat producing areas of tropics and subtropics, where the disease is nearly endemic. Human infection has been reported in pregnant women, immunocompromised patients and people exposed to animals and arthropods. The current diagnosis of haemoplasma relies on microscopic evaluation of Giemsa-stained blood smear and PCR. Although there are few published reports on the incidence of haemotropic Mycoplasma ovis infection of small ruminants in Malaysia, information on its prevalence, risk factors, severity and economic impacts is grossly inadequate. Therefore, a large-scale survey of small ruminant flocks is necessary to elucidate the current seroprevalence status and molecular characteristics of haemotropic M. ovis infection in Malaysia using ELISA and PCR sequencing technologies. In the future, surveillance programs, including vector forecast, quarantine, monitoring by periodic surveys and public enlightenment, will limit the internal and transboundary spread of M. ovis , enhance control efforts and mitigate production losses in Malaysia. Electronic supplementary material The online version of this article (10.1007/s11250-020-02357-9) contains supplementary material, which is available to authorized users.

Risk Factors and Severity of Gastrointestinal Parasites in Selected Small Ruminants from Malaysia

“…For instance, concurrent hemotropic Mycoplasma ovis infection is known to exacerbate GIP infection in sheep and goats [ 3 , 30 , 31 ]. Hemoplasmas may act in synergy with highly-pathogenic nematodes such as H. contortus and contribute to the severity of parasitic gastroenteritis (PGE) in a concurrently-infected flock [ 32 , 33 ]. The overall prevalence of parasitic infection recorded in this study is almost similar to the results of previous studies in Malaysia [ 2 , 14 , 23 ].…”

Anaemia in Lambs Caused by Mycoplasma ovis: Global and Australian Perspectives

“…M. ovis is an obligate epicellular bacteria that is mechanically transmitted by haematophagous arthropods that occur in the vicinity of livestock, including flies (e.g., Stomoxys calcitrans , Haematobia irritans , Tabanus bovinus , T. bromius , Melophagus ovinus ), midges (e.g., Culicoides brevitaris ) and mosquitoes [ 2 , 5 ]. Importantly for Australia, this also suggests the likelihood of transmission by Lucilia cuprina , the major cause of ovine myiasis [ 6 ].…”

“…Importantly for Australia, this also suggests the likelihood of transmission by Lucilia cuprina , the major cause of ovine myiasis [ 6 ]. Molecular studies have provided evidence of mechanical transmission by a range of species of ticks (e.g., Amblyomma , Hyalomma , Rhipicephalus and Haemaphysalis ) [ 2 ] and lice [ 7 ]. As arthropod vectors are considered essential in the epidemiology of haemoplasmas, seasonal changes in arthropod density and distribution influence the prevalence of M. ovis infection of sheep in Australia [ 8 ].…”

“…M. haemobos ’ in cattle, as well as M. ovis and ‘ Ca. M. haemovis ’ in sheep and goats [ 1 , 2 ]. The clinical outcome of haemoplasma infections is highly variable, ranging from life-threatening anaemia to various chronic syndromes (e.g., mild anaemia, poor performance, reproductive disorders) or even asymptomatic courses.…”

“…Haemotropic M. ovis occurs almost worldwide in small ruminant populations, also affecting a broader range of mammalian hosts, including deer, reindeer and occasionally, humans [ 2 ]. Field observations indicate that the mechanical transmission of M. ovis occurs both from the bites of haematophagous arthropods provided with access to open wounds, and iatrogenic infection from contaminated sharp instruments.…”