Comparative Inactivation of Three Different Subtypes of Avian Influenza Virus by Ozonized Water.

Avian influenza virus (AIV) causes frequent outbreaks in poultry with high morbidity and mortality. The virus can survive on different fomites, resulting in indirect transmission to susceptible hosts. We investigated the inactivation by ozonated water (O3W) of three different subtypes of AIV (H4N8, H4N6, and H9N9) on seven different fomites. All subtypes were sensitive on all fomites, but there was a slight variation in the sensitivity of different subtypes. For example, AIV H9N9 showed more than 99% reduction on denim fabric, polypropylene, and Styrofoam after 3 min of exposure. More than 97% of H4N8 was eliminated from cardboard, denim fabric, and stainless steel after 3 min of exposure. Subtype H4N6 was the least sensitive; highest inactivation (98%) was seen on cardboard and polypropylene after 3 min of exposure. In conclusion, O3W can inactivate a large percentage of AIV applied to fomites within 3 min in all tested subtypes. Interestingly, an increase in contact time to 10 min did not result in an increase in the virus inactivation rate, probably because of the low half-life of ozone. Further studies are needed to determine how the residual virus can be inactivated so that it does not pose a problem to naïve birds.

Inactivación comparativa de tres subtipos diferentes del virus de la influenza aviar mediante agua ozonizada. El virus de la influenza aviar causa frecuentes brotes en aves la avicultura con alta morbilidad y mortalidad. El virus puede sobrevivir en diferentes fómites, lo que resulta en transmisión indirecta a huéspedes susceptibles. Se investigó la inactivación mediante agua ozonizada de tres subtipos diferentes del virus de la influenza aviar (H4N8, H4N6 y H9N9) en siete fómites diferentes. Todos los subtipos fueron sensibles al agua ozonizada (O3W) en todos los fómites, pero hubo una ligera variación en la sensibilidad de los diferentes subtipos. Por ejemplo, el virus subtipo H9N9 mostró una reducción de más del 99 % en tela de mezclilla, polipropileno y espuma de poliestireno después de tres minutos de exposición. Más del 97% del subtipo H4N8 se eliminó del cartón, la mezclilla y el acero inoxidable después de tres minutos de exposición. El subtipo H4N6 fue el menos sensible; La inactivación más alta (98%) se observó en cartón y polipropileno después de tres minutos de exposición. En conclusión, el agua ozonizada puede inactivar un gran porcentaje del virus de influenza aviar aplicado a fómites en tres minutos en todos los subtipos estudiados. Curiosamente, un aumento en el tiempo de contacto a 10 minutos no resultó en un aumento en la tasa de inactivación del virus, probablemente debido a la baja vida media del ozono. Se necesitan más estudios para determinar cómo se puede inactivar el virus residual para que no represente un problema para las aves susceptibles.

Sero epidemiological study on bovine babesiosis in cattle and buffaloes in Sharkia Governorate, Egypt.

Background: Bovine babesiosis represents a serious challenge for animal health, herd production, and profitability. Understanding the epidemiology and risk factors associated with babesiosis is critical to reduce their negative impacts. Aim: Investigation of the seroprevalence and risk factors associated with Babesia bigemina (B. bigemina) and Babesia bovis (B. bovis) in five districts in Sharkia governorate using ELISA. Methods: Across-sectional research was conducted to determine the seropositivity of babesiosis by collecting a total of 352 blood samples from 250 cattle and 102 buffaloes. A multivariate logistic regression model was implemented to evaluate the strength of the risk factors associated with both Babesia species infection. Results: The seroprevalence of B. bigemina and B. bovis was 42.6% and 17.0 %, respectively. The prevalence of babesiosis in cattle was found to be 48.8% for B. bigemina and 16.8% for B. bovis. Inclusive, in buffaloes, the prevalence was 27.5% for B. bigemina and 17.6% for B. bovis. Adult animals were more vulnerable to infection with babesia than young animals by 3-5 times, respectively. Males were more susceptible to B. bigemina and B. bovis than females by 3.7 and 3.5 times. Similarly, the odds of infection in infested animals with ticks were 2-4 times higher than in animals without ticks. Conclusion: The obtained results revealed that age, sex of the animal, and tick infestation were major risk factors for the seropositivity of both Babesia species. Inclusive, there was no evidence to support the premise that seroprevalence of babesiosis is correlated with the season and species.

Molecular detection of mixed infection with peste des petits ruminants and retroviruses in Egyptian sheep and goats.

Peste des petits ruminants (PPR) is a contagious viral disease causing massive economic loss to animal industries in endemic countries including Egypt. Although a vaccine is available, coinfections can overwhelm the animal immune system and interfere with vaccine protection. Small ruminant retrovirus (SRR), including enzootic nasal tumor virus (ENTV) and Jaagsiekte sheep retrovirus (JSRV), is responsible for coinfections with PPR. Investigation of clinical cases in this study confirmed the presence of PPR virus by RT-PCR among four flocks. Sequence of five PPR amplicons revealed that all strains had 100% aa similarity and belonged to lineage IV. In addition, these strains had 98-99% nt similarity with all previous Egyptian and African strains from Sudan (MK371449) and Ethiopia (MK371449). Illumina sequencing of a representative sample showed a genome of 5753 nt compatible with ENT-2 virus with 98.42% similarity with the Chinese strain (MN564750.1). Four ORFs representing gag, pro, pol, and env genes were identified and annotated. Pro gene was highly stable while gag, pol, and env showed eight, two, and three aa differences with the reference strains. Sanger sequencing revealed that two amplicons were ENT-2 virus, and one was JSRV. ENT-2 sequences had 100% similarity with KU258870 and KU258871 reference strains while JSRV was 100% similar to the EF68031 reference strain. The phylogenetic tree showed a close relationship between the ENT of goats and the JSRV of sheep. This study highlights the complexity of PPR molecular epidemiology, with SRR that was not molecularly characterized previously in Egypt.

Molecular detection of Treponema species organisms in foremilk and udder cleft skin of dairy cows with digital dermatitis.

Identification of reservoirs and transmission routes of digital dermatitis (DD)-associated Treponema spp. is considered an effective means for controlling DD infection in dairy cows. The objective of this study is to identify and characterize the potential reservoir niches for DD-associated Treponema spp. from healthy udder cleft skin and foremilk in lactating dairy cows. A large dairy farm was visited weekly from March to July 2015. Clinical investigation revealed that a total of 25 lame cows had DD lesions located at the plantar aspect of the interdigital cleft. A total of 75 samples, three per cow, were collected including deep swabs from DD lesions (n = 25), non-aseptically collected foremilk samples (n = 25) and skin swabs from udder cleft (n = 25). Treponema spp. were identified using nested PCR assays and confirmed by DNA sequencing. Results revealed that Treponema phagedenis (T. phagedenis)-like was the most identified species in the foremilk 40% (10/25), in comparison with DD lesions and udder cleft skin samples with 32% (8/25) and 20% (5/25), respectively. On the other hand, Treponema pedis (T. pedis) was the most identified species in the udder cleft skin 80% (20/25), in comparison with DD lesions and foremilk samples with 68% (17/25) and 60% (15/25), respectively. None of the examined samples were identified by PCR as containing DNA from Treponema medium (T. medium) or Treponema vincentii (T. vincentii)-like. To the best of our knowledge, this is the first report for detection of T. phagedenis-like and T. pedis from healthy skin of udder cleft and foremilk samples. Detection of DD Treponema spp. from udder cleft skin and foremilk samples indicates that these sites could be potential reservoirs for spirochetes involved in DD. Udder cleft skin and foremilk may have a role in transmission routes of DD Treponema in dairy farms.