A systematic review of the intercontinental movement of unregulated African meat imports into and through European border checkpoints

There is an urgent need for biosurveillance of unregulated African meat imports at border points of entry in destination markets. This is underscored by recent pandemics linked to exotic wildlife products. Our objective was to catalog the quantity of meat that is informally transported from Africa into and through Europe often without any veterinary or sanitary checks. We searched and included peer-reviewed studies that contained data on the intercontinental movement of unregulated meat from the African continent. This was followed by an investigation of the reported contamination of such meat. We included fifteen airport studies with limited data on this topic. The references included in this review describe the quantity of meat found at border inspection posts and the presence of pathogens. Disease-causing pathogens were found to be present, and the results are organized into bacteria, virus, and parasite categories. The species of animal meat found in this review were linked to CITES-protected species some of which are known reservoir hosts for infectious diseases. This represents a potential and unquantified human health risk to populations along the supply chain, and a loss to biodiversity in supply countries. Meat samples described in this review were primarily found opportunistically by Customs officials, indicating that any estimate of the total quantities passing undetected through border checkpoints must remain tentative, and cannot rule out the possibility that it is indeed considerably higher. We propose a template for future studies regarding African meat imports at border points of entry. The result of this review illustrates a gap in knowledge and lacunae regarding the amount of unregulated African meat imports worldwide, the pathogens it may contain, and the resulting biodiversity loss that occurs from the intercontinental movement of this meat.

Changing epidemiology of invasive non-typhoid Salmonella infection: a nationwide population-based registry study

OBJECTIVES

Non-typhoid Salmonella (NTS) may invade beyond the intestine, causing bacteraemia, sepsis, and infection of normally sterile sites. The epidemiology of invasive NTS (iNTS) infection is under-researched. We determined trends, risk factors, serotype distribution, antimicrobial resistance (AMR), and attributable sources of iNTS infection in a high-income setting.

METHODS

22,837 records of culture-confirmed human salmonellosis cases and 10,008 serotyped Salmonella isolates from five putative animal reservoirs (pigs, cattle, broilers, layers, reptiles) in the Netherlands during 2005-2018 were retrieved from national surveillance registries. Risk factors for iNTS infection were identified using logistic regression analysis. Source attribution modelling was based on serotyping, prevalence, and exposure data.

RESULTS

The average annual percentage of iNTS infections was 4.6% (range 3.5-5.7%). An increase in iNTS infections was observed since 2012 (odds ratio (OR) 1.09, 95% confidence interval (95% CI) 1.04-1.14). Increased iNTS infection risk was associated with wintertime (OR 1.37, 95% CI 1.12-1.66), male sex (OR 1.73, 95% CI 1.51-1.99), older age (ORs: 3.27 to 16.33, depending on age groups), and living in rural areas (OR 1.54, 95% CI 1.23-1.93). While 52% of iNTS infections (n = 950) were caused by serotypes Enteritidis and Typhimurium, those displaying the highest invasiveness relative to their occurrence were Dublin (32.9%, n = 163), Panama (21.6%, n = 106), and Poona (14.1%, n = 71). Cattle were a larger source of iNTS than non-iNTS infections (12.2% vs. 7.6%). Lower AMR and multi-resistance rates were observed among iNTS (37.9%) than non-iNTS isolates (48.6%).

DISCUSSION

The increase in iNTS infections, which is reported also in other countries, is of public health and clinical concern. The underlying reasons seem to be multi-factorial in nature. iNTS infection risk depends more on the infecting serotypes and patient demographics, and less on the attributable reservoirs and AMR profiles.

Intestinal carriage of ampicillin- and vancomycin-resistant Enterococcus faecium in humans, dogs and cats in the Netherlands

Background

The prevalence of ampicillin- and/or vancomycin-resistant Enterococcus faecium (AREf and VREf) has increased in hospitalized patients in the Netherlands.

Objectives

To quantify the prevalence, risk factors and co-carriage of AREf and VREf in humans, cats and dogs in the Dutch population.

Methods

From 2014 to 2015, ∼2000 inhabitants of the Netherlands each month were randomly invited to complete a questionnaire and provide a faecal sample. Subjects owning pets were also asked to submit one dog or cat sample. Faecal samples were screened for AREf and VREf. The genetic relatedness of isolates was determined using core genome MLST. Logistic regression analysis was used to determine risk factors.

Results

Of 25 365 subjects, 4721 (18.6%) completed the questionnaire and 1992 (42.2%) human, 277 dog and 118 cat samples were submitted. AREf was detected in 29 human (1.5%), 71 dog (25.6%) and 6 cat (5.1%) samples. VREf (vanA) was detected in one human and one dog. AREf/VREf co-carriage was not detected in 388 paired samples. The use of antibiotics (OR 4.2, 95% CI 1.7-11.2) and proton pump inhibitors (OR 2.7, 95% CI 1.1-6.3) were risk factors for AREf carriage in humans. In dogs, these were the use of antibiotics (OR 2.3, 95% CI 1.1-4.6) and eating raw meat (OR 3.2, 95% CI 1.4-6.6). Core genome MLST-based phylogenetic linkage indicated clonal relatedness for a minority of human (16.7%) and pet AREf isolates (23.8%) in three clusters.

Conclusions

Intestinal carriage with AREf or VREf is rare in the Dutch general population. Although AREf carriage is high in dogs, phylogenetic linkage between human and pet AREf isolates was limited.

Long-term sequelae of sporadic cryptosporidiosis: a follow-up study

To determine the frequency of occurrence of sequelae following cryptosporidiosis. A follow-up study was performed during a case-control study for sporadic cryptosporidiosis in the Netherlands (2013–2016). Cryptosporidiosis cases were invited to complete a follow-up questionnaire 4 months after diagnosis. Using a case-crossover study design, we compared the frequencies of reported symptoms 4 months after the acute phase to those reported 4 months before the onset of illness and during illness. Frequencies of symptoms in the pre- to post-infection phases were also compared with those of a population control group. Cryptosporidium species-specific effects were also studied. Logistic regression was used to calculate adjusted odds ratios (aOR) for symptoms occurrence. Of the 731 available cases, 443 (60%) responded and 308 (42%) could be included in the follow-up study. The median age was 26 years (range 1–80); 58% were female; 30% were infected with C. hominis and 70% with C. parvum. Compared to before illness, cases were significantly more likely to report dizziness (OR = 2.25), headache (OR = 2.15), fatigue (OR = 2.04), weight loss (OR = 1.82), diarrhoea (OR = 1.50), abdominal pain (OR = 1.38) or joint pain (OR = 1.84). However, symptoms of joint pain and headache occurred among cases after illness at a rate that was not significantly different from that observed in the general population. There were no significant differences in post-infection symptom occurrence between C. hominis and C. parvum. The disease burden of cryptosporidiosis extends beyond the acute phase of the infection, with cases reporting both intestinal and extra-intestinal symptoms up to 4 months following infection.

Attribution of human infections with Shiga toxin-producing Escherichia coli (STEC) to livestock sources and identification of source-specific risk factors, The Netherlands (2010-2014)

Shiga toxin-producing Escherichia coli (STEC) is a zoonotic pathogen of public health concern whose sources and transmission routes are difficult to trace. Using a combined source attribution and case-control analysis, we determined the relative contributions of four putative livestock sources (cattle, small ruminants, pigs, poultry) to human STEC infections and their associated dietary, animal contact, temporal and socio-econo-demographic risk factors in the Netherlands in 2010/2011-2014. Dutch source data were supplemented with those from other European countries with similar STEC epidemiology. Human STEC infections were attributed to sources using both the modified Dutch model (mDM) and the modified Hald model (mHM) supplied with the same O-serotyping data. Cattle accounted for 48.6% (mDM) and 53.1% (mHM) of the 1,183 human cases attributed, followed by small ruminants (mDM: 23.5%; mHM: 25.4%), pigs (mDM: 12.5%; mHM: 5.7%) and poultry (mDM: 2.7%; mHM: 3.1%), whereas the sources of the remaining 12.8% of cases could not be attributed. Of the top five O-serotypes infecting humans, O157, O26, O91 and O103 were mainly attributed to cattle (61%-75%) and O146 to small ruminants (71%-77%). Significant risk factors for human STEC infection as a whole were the consumption of beef, raw/undercooked meat or cured meat/cold cuts. For cattle-attributed STEC infections, specific risk factors were consuming raw meat spreads and beef. Consuming raw/undercooked or minced meat were risk factors for STEC infections attributed to small ruminants. For STEC infections attributed to pigs, only consuming raw/undercooked meat was significant. Consuming minced meat, raw/undercooked meat or cured meat/cold cuts were associated with poultry-attributed STEC infections. Consuming raw vegetables was protective for all STEC infections. We concluded that domestic ruminants account for approximately three-quarters of reported human STEC infections, whereas pigs and poultry play a minor role and that risk factors for human STEC infection vary according to the attributed source.

ESBL/AmpC-producing Enterobacteriaceae in households with children of preschool age: prevalence, risk factors and co-carriage

OBJECTIVES

ESBL/AmpC-producing Enterobacteriaceae are an emerging public health concern. As households with preschool children may substantially contribute to the community burden of antimicrobial resistance, we determined the prevalence, risk factors and co-carriage of ESBL/AmpC-producing bacteria in preschool children and their parents.

METHODS

From April 2013 to January 2015, each month 2000 preschool children were randomly selected from Dutch population registries. The parents were invited to complete an epidemiological questionnaire and to obtain and send a faecal sample from the selected child and from one parent. Samples were tested for ESBL/AmpC-producing bacteria. Logistic regression was used to identify risk factors for ESBL/AmpC carriage in children and parents, and findings were internally validated by bootstrapping.

RESULTS

In total, 1016 families were included and ESBL/AmpC prevalence was 4.0% (95% CI 3.2%-5.0%); 3.5% (95% CI 2.5%-4.8%) in children and 4.5% (95% CI 3.4%-6.0%) in parents. Attending a daycare centre (DCC) was the only significant risk factor for children (OR 2.1, 95% CI 1.0-4.3). For parents, the only significant risk factor was having one or more children attending DCCs (OR 2.2, 95% CI 1.2-4.8). For parents of ESBL/AmpC-positive children the OR for ESBL/AmpC carriage was 19.7 (95% CI 9.2-42.4). Co-carriage of specific ESBL/AmpC genotypes in child and parent occurred more often than expected by chance (14.6% versus 1.1%, P < 0.001).

CONCLUSIONS

In this study, intestinal carriage with ESBL/AmpCs was detected in ∼4% of households with preschool children. DCC attendance was a risk factor in both children and parents and co-carriage of specific genotypes frequently occurred in child-parent pairs. These findings suggest household transmission or/and family-specific exposure to common sources of ESBL/AmpC-producing bacteria.

Prevalence and risk factors for patent Toxocara infections in cats and cat owners' attitude towards deworming

The prevalence of and risk factors for shedding Toxocara eggs in cats older than 6 months were determined by examining 670 faecal samples collected in 4 cross-sectional studies in the Netherlands. Additionally, cat owners provided information on their attitude towards routine deworming. Samples were examined using the centrifugal sedimentation flotation method. Overall Toxocara prevalence was 7.2 %. Multivariable logistic regression analysis revealed that young age and living in rural areas were significant risk factors for shedding Toxocara eggs. Moreover, the more time a cat was allowed to roam outdoors, the higher was its risk to shed Toxocara as compared to cats with no outdoor access at all. For 199 cats (81.6 % of cats subjected to a deworming regimen) owners provided the reason for treatment. The main reason for routine deworming (80.4 %) concerned the cat’s health and only 10.6 % of the cats were treated for public health reasons. Moreover, the generally advocated four-times-a-year deworming advice was applied on only 24.5 % of cats. We concluded that free roaming is a key factor in the acquisition of patent Toxocara infections leading to the environmental contamination with Toxocara eggs. Additionally, the knowledge of cat owners is still insufficient to expect them to make sound decisions on routine deworming.

Species composition of larvae cultured after anthelmintic treatment indicates reduced moxidectin susceptibility of immature Cylicocyclus species in horses

For the control of cyathostomins in horses, the macrocyclic lactones (MLs), moxidectin (MOX) and ivermectin (IVM) are the most commonly used anthelmintics. However, reduced activity, observed as shortening of the egg reappearance period (ERP) has been described. Shortening of the ERP may be caused by a decreased susceptibility of immature worms for MLs. Alternatively, immature worms may develop faster into egg producing adults as a result of repeated ML treatments. The species composition of the larval cultures obtained shortly after ML and pyrantel (PYR) treatment can confirm the hypothesis of decreased ML susceptibility, as this is often class-specific, whereas faster development would also occur after treatment with anthelmintics with a different mode of action. From 3 farms with a known history of shortened ERP, 8 horses per farm were selected and divided into 2 groups. The MOX-PYR-MOX group was treated twice with MOX (day 0 and 126) and once with PYR (day 84) and the IVM-PYR-IVM group was treated twice with IVM (day 0 and 98) and once with PYR (day 56). Cultured infective larvae (L3s) were counted and differentiated with the reverse line blot on pooled samples. Per cyathostomin species, the number of larvae per gram was calculated. The efficacy of all ML treatments was 100% and a shortened ERP was found on all 3 farms. The species composition of the larval cultures after ML treatment did not differ significantly from that after PYR treatment in the IVM-PYR-IVM group, but it did differ in the MOX-PYR-MOX group. The larval cultures obtained after MOX treatment consisted mostly of Cylicocyclus nassatus, while after PYR treatment Cylicostephanus longibursatus was the most abundant species. In the cultures from 42days after MOX treatment 6 cyathostomin species from 3 genera were found on the farm with the lowest activity (farm 1), while on the farm with the highest activity (farm 3) only 3 species from one genus were found in the same number of examined L3s. The high numbers of L3s of Cylicocyclus species 42days after MOX treatment and the low numbers 42days after PYR treatment can be explained by reduced susceptibility of the immature worms to MOX, but not by a faster development. In conclusion, shortening of the ERP following MOX treatment is most likely a process in which an increasing number of immature worms from an increasing number of species is becoming less susceptible to the active compound.

Potential causative agents of acute gastroenteritis in households with preschool children: prevalence, risk factors, clinical relevance and household transmission

Acute gastroenteritis (AGE) morbidity remains high amongst preschool children, posing a significant societal burden. Empirical data on AGE-causing agents is needed to gauge their clinical relevance and identify agent-specific targets for control. We assessed the prevalence, risk factors and association with symptoms for enteropathogens in households with preschool children. A monthly-repeated cross-sectional survey of enteropathogens in households with preschool children was performed. A parent-child pair per household (n = 907 households) provided faecal samples and reported their symptoms and potential risk exposures. Samples were tested by multiplex reverse transcription polymerase chain reaction (RT-PCR) for 19 enteropathogens. Associations were assessed using logistic regression. 28.3 % of children (n = 981) and 15.6 % of parents (n = 971) carried pathogenic bacteria and/or Escherichia coli-associated pathogenicity genes, and 6.5 % and 3.3 % carried viruses, respectively. Giardia lamblia (4.6 % of children, 2.5 % of parents) and Dientamoeba fragilis (36 %, 39 %, respectively) were the main parasites, and were associated with pet exposure. Living in rural areas was associated with carriage of pathogenic E. coli, norovirus I and D. fragilis. Pathogenic E. coli was associated with summertime and livestock exposure. Attending day-care centres increased the risk of carrying norovirus, sapovirus and G. lamblia. Viruses occurred mainly in winter and were associated with AGE symptoms. Child-parent associations were found for bacterial pathogenicity genes, viruses, G. lamblia and D. fragilis. Enteropathogens spread widely in households with preschool children, particularly viruses, which more often cause symptoms. While bacteria predominate during summer and in those exposed to livestock, viruses predominate in wintertime and, like G. lamblia, are widespread amongst day-care centre attendees.

Seroprevalence and factors associated with equine herpesvirus type 1 and 4 in Spanish Purebred horses in Spain

Equine herpesvirus type 1 (EHV-1) and type 4 (EHV-4) have a worldwide distribution and cause respiratory disease, abortion, neonatal death and myeloencephalopathy in susceptible horses. Given the scarcity of serological EHV-1/EHV-4 data in Spain, the objective of this cross-sectional study was to estimate the seroprevalence of EHV-1/EHV-4 and to identify potential horse-level and stud farm-level factors associated with EHV-1/EHV-4 in the breeding Spanish Purebred (SP) horse population in central Spain. Serum samples from 334 SP unvaccinated horses, collected between September 2011 and November 2013 at 30 stud farms, were tested using a commercially available EHV-1/EHV-4 antibody ELISA and seroneutralisation as the World Organisation for Animal Health reference confirmation test. Data on factors putatively associated with seropositivity to EHV-1/EHV-4 were collected via a questionnaire and examined using logistic regression analysis. EHV-1/EHV-4 seroprevalence in the SP breeding population in central Spain, standardised for the sex distribution of the reference horse population, was 53.9 per cent (95 per cent confidence interval 44.0 per cent to 63.8 per cent). Increasing age, southern location of the stud farm, temperate climate during the summer, and a smaller surface area used for breeding activities in the farm were associated with increased odds for EHV-1/EHV-4 seropositivity, whereas EHV-1/EHV-4 vaccination of other resident horses and separation of breeding mares from youngsters were protective factors.

Seroprevalence and factors associated with seropositivity to equine arteritis virus in Spanish Purebred horses in Spain

REASONS FOR PERFORMING STUDY

Equine viral arteritis (EVA), a disease caused by infection with the equine arteritis virus (EAV), is present in many European countries. In Spain, the last confirmed outbreak was reported in 1992 and there is a paucity of seroprevalence studies. The disease has a major impact on the equine breeding industry, which is mainly represented by Spanish Purebred (SP) horses in Spain.

OBJECTIVES

To estimate the seroprevalence of EAV in the breeding SP horse population in central Spain and identify potential horse and studfarm level factors associated with seropositivity to EAV.

STUDY DESIGN

Cross-sectional study.

METHODS

Individual serum samples from 555 SP horses, collected between September 2011 and November 2013 at 35 studfarms, were tested using a commercially available EAV antibody ELISA and seroneutralisation as the World Organisation for Animal Health reference confirmation test for samples with positive and equivocal results. Data on factors putatively associated with seropositivity to EAV were collected via a questionnaire and examined using random effects logistic regression for analysis of clustered data.

RESULTS

Equine arteritis virus seroprevalence in the SP breeding population in central Spain standardised for the sex distribution of the reference horse population, was estimated to be 16.8% (95% confidence interval 5.2-28.5%). Increasing numbers of breeding mares on the studfarm and increasing percentage of mares with reproductive problems during the last 12 months were identified as being positively associated with EAV seropositivity. Mares vaccinated against Equine herpesvirus-1 (EHV-1) and/or -4 (EHV-4) were also positively associated with EAV seropositivity.

CONCLUSIONS

These findings are of importance to ensure appropriate biosecurity measures for studfarms are carried out and may help facilitate the development of an EVA surveillance programme in the SP breeding horse population.

Distribution of Salmonella enterica isolates from human cases in Italy, 1980 to 2011

We describe trends of Salmonella enterica serovars isolated from humans in Italy from January 1980 to December 2011. A total of 229,279 Salmonella isolates were reported during this period. Serovars Enteritidis, Typhimurium, Infantis, Derby, 4,[5],12,:i:-, and Napoli accounted for 135,783 (59%) of these isolates. Temporal trends from 2000 to 2011 varied by serovar: Enteritidis and Infantis decreased significantly (with a mean of -3.0% and -2.8% isolates per year, respectively, p<0.001); Typhimurium remained stable; while 4,[5],12:i:-, Derby and Napoli increased significantly (+66.4%, p<0.001; +8.1%, p<0.001; and +28.2%, p<0.05, respectively). Since 2000, Enteritidis fell consistently below Typhimurium, which is the most reported serovar in Italy in contrast to the international situation where Enteritidis still ranks at the top despite its significant decrease. Most serovars showed a marked seasonality, increasing over the summer months and peaking in August/September. Typhimurium, 4,[5],12:i:-, and Napoli were most likely to be isolated from children, whereas Enteritidis, Derby, and Infantis from adults. We conclude that the applied control measures are not equally efficient against the considered Salmonella serovars and that sources of infection other than those of Enteritidis (laying hens and eggs) have become increasingly important. Further investigations on the emerging serovars and on the causes related to their emergence are needed to define and implement newly tailored control measures.

Surveillance of acute infectious gastroenteritis (1992–2009) and food-borne disease outbreaks (1996–2009) in Italy, with a focus on the Piedmont and Lombardy regions

We describe trends in the occurrence of acute infectious gastroenteritis (1992 to 2009) and food-borne disease outbreaks (1996 to 2009) in Italy. In 2002, the Piedmont region implemented a surveillance system for early detection and control of food-borne disease outbreaks; in 2004, the Lombardy region implemented a system for surveillance of all notifiable human infectious diseases. Both systems are internet based. We compared the regional figures with the national mean using official notification data provided by the National Infectious Diseases Notification System (SIMI) and the National Institute of Statistics (ISTAT), in order to provide additional information about the epidemiology of these diseases in Italy. When compared with the national mean, data from the two regional systems showed a significant increase in notification rates of non-typhoid salmonellosis and infectious diarrhoea other than non-typhoid salmonellosis, but for food-borne disease outbreaks, the increase was not statistically significant. Although the two regional systems have different objectives and structures, they showed improved sensitivity regarding notification of cases of acute infectious gastroenteritis and, to a lesser extent, food-borne disease outbreaks, and thus provide a more complete picture of the epidemiology of these diseases in Italy.

Surveillance of acute infectious gastroenteritis (1992-2009) and food-borne disease outbreaks (1996-2009) in Italy, with a focus on the Piedmont and Lombardy regions

We describe trends in the occurrence of acute infectious gastroenteritis (1992 to 2009) and food-borne disease outbreaks (1996 to 2009) in Italy. In 2002, the Piedmont region implemented a surveillance system for early detection and control of food-borne disease outbreaks; in 2004, the Lombardy region implemented a system for surveillance of all notifiable human infectious diseases. Both systems are internet based. We compared the regional figures with the national mean using official notification data provided by the National Infectious Diseases Notification System (SIMI) and the National Institute of Statistics (ISTAT), in order to provide additional information about the epidemiology of these diseases in Italy. When compared with the national mean, data from the two regional systems showed a significant increase in notification rates of non-typhoid salmonellosis and infectious diarrhea other than non-typhoid salmonellosis, but for foodborne disease outbreaks, the increase was not statistically significant. Although the two regional systems have different objectives and structures, they showed improved sensitivity regarding notification of cases of acute infectious gastroenteritis and, to a lesser extent, food-borne disease outbreaks, and thus provide a more complete picture of the epidemiology of these diseases in Italy.