Antimicrobial Resistance Profiles and Genes of Staphylococci Isolated from Mastitic Cow’s Milk in Kenya

Abstract

Increasing numbers of potentially zoonotic multidrug-resistant (MDR) staphylococci strains, associated with mastitis in dairy cows, are being reported globally and threaten disease management in both animal and human health. However, the prevalence and antimicrobial resistance profiles of these strains, including methicillin-resistant staphylococci (MRS), in Kenya is not well known. This study investigated the drug resistance profiles and genes carried by 183 staphylococci isolates from 142 dairy cows representing 93 farms recovered from mastitis milk of dairy cows in two selected counties in Kenya. Staphylococci isolates were characterized by phenotypic characteristics, polymerase chain reaction (PCR) amplification, partial sequencing and susceptibility testing for 10 antimicrobial drugs. Detection of seven resistance genes to the various antimicrobial drugs was conducted using PCR. Overall, phenotypic resistance among the staphylococci ranged between 66.1% for ampicillin and 3.5% for fluoroquinolones. Twenty-five percent (25%) of S. aureus and 10.8% of the coagulase-negative staphylococci (CoNS) isolates, were methicillin-resistant staphylococci phenotypically (defined as resistance to cefoxitin disk diffusion). The most common genes found in S. aureus and CoNS were blaZ and strB at 44.3% and 26%, and 78% and 50%, respectively. MDR was observed in 29.67% and 16.3% of S. aureus and CoNS, respectively. These findings pose a threat to bovine mastitis treatment and management as well as human health.

Multiple antibiotic resistance and virulence factors of Staphylococcus aureus strains isolated from dairy farms in South Sulawesi, Indonesia

“…This study did not report the presence of the ermB gene from the animal samples (raw milk) or the qnrS gene from human samples (skin swab of the farmer). Contrastingly, previous studies reported the presence of the antibiotic resistance genes ermB and qnrS from animal and human samples, respectively (Abdu and Mirabeau 2019;Mbindyo et al 2021). There is a discrepancy between ARGs and phenotypic confirmation.…”

“…This finding is in line with the results of previous research in Surabaya, Indonesia (Tyasningsih et al 2019). A study by Mbindyo et al (2021) reported the frequency of resistance to antibiotics ampicillin (71.4%), tetracycline (21%), erythromycin (25.2%) in Kenya. Meanwhile, a previous study by Liu et al 2017 reported the incidence of resistance to antibiotics penicillin G (85.2%), ampicillin (79.6%), tetracycline (13%), and erythromycin (46.3%) in China.…”

Relationship between Biofilm Formation and Antibiotic Resistance and Adherence Genes in Staphylococcus aureus Strains Isolated from Raw Cow Milk in Shahrekord, Iran

“…This alarming rate of resistance to beta-lactam antibiotics is corroborated by some recent findings [ 54 , 55 ] and can be explained by the common use of β -lactams in the treatment of bovine mastitis [ 56 ]. A study carried out in Kenya by Mbindyo et al found that 71.4% of S. aureus strains exhibited resistance to ampicillin [ 57 ]. Another study reported that the frequency of resistance to penicillin G was 85.2% [ 58 ].…”

Prevalence and antimicrobial resistance profiling of Staphylococcus aureus isolated from traditional cheese in Yunnan, China

“…Meanwhile, a Brazilian study found a lower prevalence of S. aureus isolates (29%) (Kayili and Sanlibaba 2020;Pereira et al 2018). Several efflux pump genes are identified as responsible for MDR mechanisms (Mahmood et al 2016;Mbindyo et al 2021). The presence of a non-native gene involved in the peptidoglycan biosynthesis pathway and producing penicillin-binding proteins (PBPs), a meshlike polymer surrounding the bacterial cell, has also been suggested as a possible explanation for the high prevalence of S. aureus resistance occurrences (Peacock and Paterson 2015;Stapleton and Taylor 2002).…”