Epidemiology and Prevention of Feline Gastrointestinal Virus Infections A Discussion Centered on Glinx Data Analysis

Introduction

 

As close companions to humans, the health issues of pet cats are increasingly drawing the attention of veterinarians and pet enthusiasts. Pathogens such as Feline Parvovirus (FPV), Feline Coronavirus (FCoV), Feline Astrovirus (FeAstV), Feline Chaphamaparvovirus (FeChPV), and Feline Bocavirus (FBoV) have raised concerns among clinical veterinarians regarding gastrointestinal problems in cats. This article will discuss the epidemiology, infection rates, and incidence of mixed infection of these viruses, as well as emphasize the necessity of virus testing.

 

 

Epidemiology and Research Overview of Feline Gastrointestinal Viruses

 

Feline Parvovirus (FPV)

 

 

Feline Parvovirus, also known as feline panleukopenia virus (FPV) is highly contagious and primarily spreads through the feces and secretions of infected and recovering cats. It can be transmitted to fetuses via the placenta, and certain blood-sucking insects may also aid in its transmission. In China, the highest infection rates occur during the spring and winter [1]. Cats of all ages can be infected, with kittens under 10 months of age being the most susceptible, showing infection rates of up to 70%. The mortality rate is highest in kittens under 5 months old, reaching 80% to 90%. Stress can increase the incidence of the disease. The virus is resistant to various disinfectants. Despite the use of common household disinfectants, cats may still become infected, particularly during the acute infection period when high concentrations of the virus can be detected in vomit and feces. Infected cats may be asymptomatic but can shed the virus long term, similar to Canine Parvovirus. FPV can remain infectious in the environment for weeks to months, and contaminated objects are highly infectious, playing a crucial role in virus transmission. Indoor cats with no history of contact with other animals also have a risk of infection [2]. All felids and some non-felid animals can also be infected. FPV is distributed globally and exhibits significant geographic clustering [3].

 

Feline Coronavirus (FCoV)

 

Feline Coronavirus (FCoV) infections are widespread in cat populations, with 20% to 60% of pet cats carrying FCoV antibodies. Cats living in shelters or multi-cat households can have an antibody positivity rate close to 100%. FCoV is highly contagious. In multi-cat environments , 75% to 100% of cats can become infected and shed the virus long term. Feline Coronavirus has two clinical forms: Feline Enteric Coronavirus (FECV) and Feline Infectious Peritonitis Virus (FIPV). FECV has low pathogenicity and a low mortality rate. Most infected cats are asymptomatic or exhibit mild enteritis, while a few show signs of fever, reduced appetite, or dehydration. FECV infections are common in healthy cat populations, with an incidence rate as high as 90% among stray cats. FIPV arises from mutations of FECV and causes Feline Infectious Peritonitis (FIP). FIPV is highly virulent, leading to fatal infectious peritonitis in infected cats, along with enteritis, mild to severe eye diseases, and neurological disorders [4].

 

Feline Astrovirus

 

Astroviruses (AstVs) are small, non-enveloped, single-stranded RNA viruses characterized by a star-like ultrastructure. The family Astroviridae contains two genera, Mamastrovirus and Avastrovirus, which infect mammals and birds, respectively. Feline Astrovirus (FeAstV) belongs to the Mamastrovirus genus and was first identified in 1981 in the United States through electron microscopy in feline diarrhea samples. Reports indicate that naturally infected domestic cats exhibit symptoms such as vomiting, diarrhea, loss of appetite, dehydration, and fever. Animals typically recover fully within 7 to 10 days after symptom onset. Experimental reproduction of intestinal disease using the Bristol strain of FeAstV was achieved in specific pathogen-free kittens.  In the current study, a dual infection by FAstV and FPV was diagnosed in a cat presenting with severe gastroenteritis. Possible interactions and synergistic mechanisms of enhancement of viral pathogenicity may not be ruled out.

 

 

A study in Japan conducted genetic testing for FeAstV and FPV—both known feline gastrointestinal viruses—on the feces of 204 domestic cats with gastrointestinal symptoms [5]. The study found that the detection rate of FeAstV was significantly higher in winter (44.4%) compared to other seasons, and the detection rate in kittens under one year old (27.8%) was higher than in cats one year and older (12.4%) (P<0.05). Similar seasonal patterns have been observed in human astrovirus outbreaks, suggesting that the stability of the virus may be influenced by temperature.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Feline Chaphamaparvovirus (FeChPV)

 

Feline chaphamaparvovirus (FeChPV) is a novel parvovirus, first discovered in a multi-facility feline shelter in Canada in 2019, during an outbreak of acute gastroenteritis (AGE) in cats, and detected at high prevalence (47.0%) in faecal samples[6]. In a case-control study investigating whether this newly identifiedl genus of parvoviruses might act as an intestinal pathogen, samples from cats with and without AGE symptoms were screened. The study found that FeChPV DNA had a high detection rate in clinical cases (36.8%, 14/38), making it the most commonly identified enteric virus, followed by Feline Parvovirus (23.7%, 9/38), Feline Coronavirus (5.3%, 2/38), Feline Enteric Virus (5.3%, 2/38), and Norovirus (5.3%, 2/38). The statistically significant difference in FeChPV infection rates between the case group and the control group suggests that this virus may be associated with acute intestinal disease [7].

 

 

 

 

 

 

 

 

Feline Bocavirus (FBoV)

 

Feline Bocavirus (FBoV) belongs to the family Parvoviridae, subfamily Parvovirinae, and genus Bocaparvovirus. In 2012, Lau et al. conducted a study using PCR to detect BoVs in domestic cats and dogs in Hong Kong, testing a total of 1,503 feline and 1,384 canine fecal, nasal swab, blood, and kidney samples. Bocavirus was detected in all clinical samples from the cats, marking the first identification of FBoV in cat populations. In 2015, Liu et al. detected FBoV-positive samples in the feces of cats with diarrhea in Harbin, with sequencing confirming the prevalent strain as FBoV-1, further proving the circulation of FBoV in domestic cats in China [4][8]. Some studies suggest that FBoV is pathogenic in young cats (one year old or younger), causing diarrhea and possibly being associated with severe enteritis and hemorrhagic enteritis [9].

 

 

GlinX Data Analysis

 

According to GlinX data, from December 2023 to February 2024, the positive detection rate of the feline gastrointestinal virus five-in-one panel (Feline Parvovirus, Feline Coronavirus, Feline Astrovirus, Feline Chaphamaparvovirus, Feline Bocavirus) reached 78.21% (2,190/2,800). Among these, Feline Coronavirus had the highest positive rate at 52.46%, followed by Feline Parvovirus at 26.96%. Feline Astrovirus and Feline Chaphamaparvovirus showed positive rates of 19.61% and 17.89%, respectively, while Feline Bocavirus had a positive rate of 8.14%. In addition to Feline Parvovirus and Feline Coronavirus, newly identified viruses are also becoming common sources of infection. Mixed infection (35%) is prevalent, meaning that approximately 1 in 3 cats with gastrointestinal issues has mixed infections. Mixed infection accounted for about 44.75% (980/2,190) of positive cases. The mixed infection with multiple viruses increases the difficulty of clinical diagnosis and treatment, and may lead to severe complications.

 

 

 

Total tests	2800
Negative cases	610
Positive cases	2190
Positive rate	78.21%
Single infection cases	1210
Single infection rate	43.21%
Mixed infection cases	980
Mixed infection rate	35.00%

 

表1. 基灵23年12月至24年2月消化道病毒五联总体检出情况

Table 1. Results of GlinX Feline Gastrointestinal Virus Five-In-One Panel from December 2023 to February 2024

 

 

Virus	Positive cases	Positive rate	Single infection cases	Mixed infection cases
FPV	755	26.96%	202	553
FCoV	1469	52.46%	686	783
FeAstV	549	19.61%	177	372
FeChPV	501	17.89%	126	375
FBoV	228	8.14%	19	209

 

表2 基灵23年12月至24年2月消化道病毒五联各病原检出情况

Table 2. Detection Results of Each Pathogen in GlinX Feline Gastrointestinal Virus Five-In-One Panel from December 2023 to February 2024

 

表3 基灵23年12月至24年2月消化道病毒五联病原混合感染情况

Table 3. Mixed Infection Status of Pathogens tested by GlinX Feline Gastrointestinal Virus Five-In-One Panel from December 2023 to February 2024

 

 

 

 

Reasons for Virus Testing

 

 

1.       Early Detection and Treatment: Early detection allows for timely treatment of infected cats, helping to suppress the progression of the disease.

 

2.       Prevention of Transmission: Feline viral diseases can spread through contact, including direct contact or via formites. Early diagnosis and treatment are crucial for preventing disease transmission. Virus testing can facilitate the health management of infected individuals and plays a key role in controlling the spread of disease within cat populations.

 

3.       Enhancing Animal Welfare: Testing can identify and manage chronic or latent infections, improving the quality of life for animals.

 

 

Discussion

 

GlinX data analysis reveals the epidemiology and infection rates of feline gastrointestinal viral diseases. In addition to common viruses, the detection rate of newly emerging viral infections is also notable, and there is a high rate of mixed infection. For cats with acute or chronic diarrhea in clinical practice, viral infections should be considered alongside other causes such as dietary factors, bacterial infections, allergies, and parasites, and virus testing should be included in the diagnosis process.

 

References 

 

[1]        Cao, L., Chen, Q., Ye, Z., Li, J., Zhang, Y., Wang, Y., Chen, L., Chen, Z., Jin, J., Cao, S., Zhao, H., Li, Q., & Zhou, D. (2023). Epidemiological survey of feline viral infectious diseases in China from 2018 to 2020. Animal Research and One Health, 1(2), 233–241.

[2] Kruse B D, Unterer S, Horlacher K, et al. Prognostic factors in cats with feline  panleukopenia[J]. Journal of veterinary internal medicine, 2010, 24(6): 1271-1276.

[3]        刘昱欣, 李卓宸, 吕爽, et al. 猫泛白细胞减少症病毒研究进展 [J]. 特产研究, 2023, 45(05): 147-53.

[4]        李春华, 于瑞嵩, 周宗清. 犬猫冠状病毒病 [J]. 上海畜牧兽医通讯, 2023, (02): 1-9+80.

[5]  Soma T, Ogata M, Ohta K, Yamashita R, Sasai K. Prevalence of astrovirus and parvovirus in Japanese domestic cats. J Vet Med Sci. 2020 Sep 7;82(9):1243-1246.

[6]        Li, Y., Gordon, E., Idle, A., Altan, E., Seguin, M. A., Estrada, M., Deng, X., & Delwart, E. (2020). Virome of a feline outbreak of diarrhea and vomiting includes bocaviruses and a novel chapparvovirus. Viruses, 12(5), 506.

[7]        LIU X, LI S, LIU X, et al. Establishment of SYBR green I-based quantitative real-time polymerase chain reaction for the rapid detection of a novel Chaphamaparvovirus in cats [J]. 3 Biotech, 2022, 12(4): 91.

[8] Chunguo LIU, Fei LIU, Zhigang LI, Liandong QU, Dafei LIU, First report of feline bocavirus associated with severe enteritis of cat in Northeast China, 2015, Journal of Veterinary Medical Science, 2018, Volume 80, Issue 4, Pages 731-735.

[9] Wang Y, Guo X, Li W, Cui Y, Zhang D, Xu F, Jiang S, Zhou T. Phylogenetic analysis and evolution of feline bocavirus in Anhui Province, eastern China. Comp Immunol Microbiol Infect Dis. 2021 Aug;77:101676.