FlagT4G Vaccine Prevents Transplacental Transmission of Highly Virulent Classical Swine Fever Virus after Single Vaccination in Pregnant Sows.

The transplacental transmission of CSFV and the resulting persistent congenital infection in newborn piglets have been abundantly discussed in pregnant sows suffering from virus infection. Importantly, the availability of safe commercial vaccines with proven efficacy to prevent the generation of congenital and postnatal persistent infections in pregnant sows are critical tools for controlling the disease in CSF endemic areas. Here, we demonstrate the high efficacy of a single dose of the recombinant FlagT4G vaccine to provide solid protection in pregnant sows against transplacental transmission of a highly virulent CSFV. Pregnant sows vaccinated with FlagT4G at 44 days of gestation elicited a strong CSFV-specific antibody response, with neutralizing antibody levels above those required for protection against CSFV. Importantly, after the challenge with a highly virulent CSFV, all foetuses from FlagT4G-vaccinated sows lacked CSF macroscopic lesions and showed a complete absence of the challenge virus in their internal organs at day 79 of gestation. Therefore, pregnant sows safely vaccinated with FlagT4G without affecting reproductive efficacy are efficaciously protected, along with their foetuses, against the infection and disease caused by a CSFV virulent field strain.

Molecular prevalence of Toxoplasma gondii and Trypanosoma evansi in recently calved female cattle from Phayao, Thailand.

Background and Aim: Toxoplasma gondii and Trypanosoma evansi, the zoonotic protozoa responsible for toxoplasmosis and trypanosomiasis, are significant threats to the productivity and financial stability of livestock farming. T. gondii can be transmitted horizontally through ingestion of fecal oocysts and T. evansi through arthropod vectors. In addition, both species can be transmitted from mother to fetus through the placenta. This study aimed to assess the molecular prevalence of T. gondii and T. evansi transplacental-transmitted protozoans and to identify the epidemiological risk factors in recently calved female cattle across Phayao, Thailand. Materials and Methods: We collected 106 bovine placentas from beef and dairy cow full-term pregnancies in Phayao, Thailand. T. gondii and T. evansi DNA were detected using targeted B1 gene and expression site-associated gene (ESAG) species-specific polymerase chain reaction (PCR), respectively. Results: Forty-three placentas were positive for T. gondii B1 PCR, whereas only one was positive for T. evansi ESAG PCR, resulting in an overall prevalence of transplacental-transmitted protozoan infection of 41.5% (44/106). The prevalence of T. gondii and T. evansi was 40.6% (43/106) and 0.9% (1/106), respectively. No significant correlation was found between T. gondii infection and various risk factors, including locality, age, and cattle type. Conclusion: The prevalence of transplacental-transmitted protozoan T. gondii infection was high among female cattle in Phayao, Thailand, whereas the prevalence of T. evansi infection was notably lower. Although the conventional modes of transmission differ between these two parasites, the transplacental transmission of T. evansi and especially T. gondii may play a crucial role in the persistence of these protozoan species in this area.

Transplacental transfer of anti-SARS-CoV-2 neutralizing antibodies in comparison to other pathogens total antibodies.

BACKGROUNDS: Due to immaturity of their immune system, passive maternal immunization is essential for newborns during their first months of life. Therefore, in the current context of intense circulation of SARS-CoV-2, identifying factors influencing the transfer ratio (TR) of neutralizing antibodies against SARS-CoV-2 (NAb) appears important. METHODS: Our study nested in the COVIPREG cohort (NCT04355234), included mothers who had a SARS-CoV-2 PCR positive during their pregnancy and their newborns. Maternal and neonatal NAb levels were measured with the automated iFlash system. RESULTS: For the 173 mother-infant pairs included in our study, the median gestational age (GA) at delivery was 39.4 weeks of gestation (WG), and 29.7 WG at maternal SARS-CoV-2 infection. Using a multivariate logistic model, having a NAb TR above 1 was positively associated with a longer delay from maternal positive SARS-CoV-2 PCR to delivery (aOR 1.09, 95% CI: 1.03 - 1.17) and with a later GA at delivery (aOR = 1.58, 95% CI: 1.09 - 2.52). It was negatively associated with being a male newborn (aOR 0.21, 95% CI: 0.07 - 0.59). In 3rd trimester SARS-CoV-2 infected mothers, NAb TR was inferior to VZV, toxoplasmosis, CMV, measle and rubella's TR. However, in 1st or 2nd trimester infected mothers, only measle TR was different from NAb TR. CONCLUSION: Male newborn of mothers infected by SARS-CoV-2 during their pregnancy appear to have less protection against SARS-CoV-2 in their first months of life than female newborns. Measle TR was superior to NAb TR even in case of 1st or 2nd trimester maternal SARS-CoV-2 infection. Future studies are needed to investigate possible differences in transmission of NAb following infection vs vaccination and its impact on TR.

Experimental infection with Neospora caninum in Texel ewes at different stages of gestation.

In this study Texel sheep, at different stages of pregnancy, were experimentally infected with Neospora caninum. Eleven ewes, seronegative for N. caninum and Toxoplasma gondii, were inoculated 30 days before breeding (Group A), or at 65, 100, and 120 days of gestation (Groups B, C, and D). The group E (control) was inoculated with PBS. Blood samples were collected at -2, 2, 5, and 7 days post-infection (dpi), and weekly up to 42 dpi, for hematology, parasitemia (PCR), and serology (RIFI) assessments. Blood and tissue samples were collected from the lambs for molecular and histological analyses. All animals in Groups B, C, and D were seroconverted, whilst those in groups A and E remained seronegative. Parasitic DNA was detected in the blood of two ewes (groups B and D) and a lamb (group D), and in the brain of a lamb (group B). The parasitemia-positive ewe in group B delivered a weak and seropositive lamb, and had parasitic DNA in its placenta. These results confirm the vertical transmission of N. caninum in ewes inoculated at the beginning and end of pregnancy. The absence of abortions and other clinical signs suggest that Texel sheep may potentially have resistance to N. caninum.

Mouse models of Zika virus transplacental transmission.

Seven years after the onset of the Zika virus (ZIKV) epidemic in the Americas, longitudinal studies are beginning to demonstrate that children infected in utero and born without severe birth defects exhibit motor skill deficits at up to 3 years of age. Long term health and socioeconomic impacts of fetal ZIKV infection appear imminent. ZIKV continues to circulate in low levels much as the virus did for decades prior to the 2015 epidemic, and the timing of the ZIKV outbreak is unknown. Thus, in the continued absence of ZIKV vaccines or antivirals, small animal models of ZIKV transplacental transmission have never been more necessary to test antiviral strategies for both mother and fetuses, and to elucidate mechanisms of immunity at the maternal-fetal interface. Here we review the state of ZIKV transplacental transmission models, highlight key unanswered questions, and set goals for the next generation of mouse models.

Consequences of Transplacental Transmission of the SARS-CoV-2 Virus: A Single-Center Experience.

The issues of vertical viral transmission from mother to fetus and the potential complications caused by SARS-CoV-2 coagulopathy are still unclear. There are few literature data about the vertical transmission of SARS-CoV-2 and health outcomes in neonates born to mothers with symptomatic or asymptomatic coronavirus disease, with the existing data based on small sample sizes. This case series study consists of two newborn children (one pre-term and one term) who were born to SARS-CoV-2-positive mothers and admitted to the neonatal intensive care unit a few hours after birth. One child had cyanotic changes that affected the entire left leg and the left forearm, with multiple livid changes on the front of the chest and abdomen, the right upper arm, right thigh, neck, and face, and one child had an altered umbilical cord. The first child was treated conservatively, and the second child was treated surgically.

Experimental Neospora caninum Infection in Pregnant Cattle: Different Outcomes Between Inoculation With Tachyzoites and Oocysts.

Neospora caninum is a globally distributed abortifacient protozoan of cattle. Experimental infections with N. caninum in cattle have provided valuable information on host-parasite interaction and immunopathogenesis. Experimental infection of pregnant cows has been reported in about 20 articles, with most studies using cultured parasite tachyzoites as the inoculum. Only three experimental studies have been conducted in pregnant cows using the parasite's oocysts which are shed by dogs, in large part because transmission experiments using oocysts take more time and are more complex and expensive than experiments using tachyzoites. In this minireview, we discuss differences between N. caninum tachyzoites and oocysts as inocula for experimental infection of pregnant cows, as well as the route animals are inoculated.

Detection of bovine gammaherpesvirus 6 in tissues of aborted fetuses from dairy cows concomitantly infected by Histophilus somni.

Bovine gammaherpesvirus 6 (BoGHV6), formerly known as bovine lymphotropic virus, is a member of the Macavirus genus, subfamily Gammaherpesvirinae, family Herpesviridae, that was initially associated with proliferative diseases in cattle. While the Macavirus genus contains agents, including alcelaphine gammaherpesvirus 1 (AlGHV1), ovine gammaherpesvirus 2 (OvGHV2), and caprine gammaherpesvirus-2 (CpGHV2), known to cause malignant catarrhal fever (MCF), and are collectively referred to as MCF virus (MCFV) group of organisms, diseases and/or clinical syndromes have not been associated with BoGHV6 and porcine lymphotropic herpesvirus (PLHV). This report investigated the occurrence of BoGHV6 in tissues of aborted dairy fetuses known to be infected by Histophilus somni to identify possible disease patterns associated with infection by this Macavirus. A nested-PCR (nPCR) assay was used to amplify the BoGHV6 polymerase gene from multiple tissues of 13 fetuses and the cow of one of these which were derived from seven dairy herds located in three geographical regions of Brazil. Direct sequencing confirmed the results of the nPCR assays. Additionally, all fetal tissues were previously investigated for the presence of H. somni, Listeria monocytogenes, Neospora caninum, Brucella abortus, Leptospira spp., bovine alphaherpesvirus 1, and bovine viral diarrhea virus (BVDV) by PCR and/or RT-PCR assays. The nPCR assay amplified BoGHV6 DNA from fetuses of most dairy herds (85.7%; 6/7) investigated, resulting in the amplification of BoGHV6 from 76.9% (10/13) of all fetuses evaluated from two geographical and important cattle-producing regions of Brazil. Furthermore, only BoGHV6 was identified in the spleen (n = 3), myocardium, and kidney (n = 2) of five fetuses, and BoGHV6 was the only agent associated with myocarditis in one of these. Nevertheless, dual, triple, and quadruple infections (including BVDV, B. abortus, and N. caninum) were identified in fetuses that were concomitantly infected by H. somni. Phylogenetic analysis revealed that the strain herein identified has 100% nucleotide (nt) sequence identity with wild type strains of BoGHV6 circulating in ruminants from Brazil and 99.8% nt identity with the reference strain of BoGHV6 but was 72.2-73.3% and 67.4-68.2% different from members of the MCFV group and PLHV, respectively. These results demonstrated that 76.9% of the fetuses evaluated were infected by BoGHV6, most likely via vertical infection resulting in transplacental transmission. Considering that most fetuses were concomitantly infected by BoGHV6 and H. somni the real impact of this viral infection cannot be efficiently determined. However, since BoGHV6 was the only pathogen identified in the myocardium of one fetus with myocarditis by histopathology, the possible participation of this Macavirus in the etiopathogenesis of the myocardial disease observed in this fetus cannot be ignored or discarded. However, the mere amplification of BoGHV6 DNA from the myocardium is not enough to establish a definite association between cause and effect, since in situ evaluations and experimental studies would be needed to confirm this agent in the etiopathogenesis of fetal diseases and/or abortions in cattle. Consequently, additional studies are needed to determine the exact role, if any, of BoGHV6 in the development of fetal disease, and possibly fetal mortality.

Congenital Neurological Disease Associated With HoBi-like Pestivirus Infection in a Newborn Dairy Calf From Brazil.

HoBi-like pestivirus (HoBiPeV) has been reported in several biological samples from cattle worldwide, but there are no descriptions of this virus associated with neurological symptoms. This report described the first occurrence of neurological disease associated with HoBiPeV in a newborn dairy calf. A mixed-breed Holstein calf had severe neurological symptoms at birth and died at 21 days old. The tissue fragments (central nervous system (CNS), myocardium, liver, kidney, lung, intestine, and spleen) were submitted to reverse transcription (RT)-PCR assay for the partial 5'-untranslated region (5'UTR) and N-terminal autoprotease (Npro) gene of the pestivirus genome, and the CNS tissue fragments were submitted to histopathological and immunohistochemical evaluation. The RT-PCR assay indicated that the kidney, CNS, and intestinal tissue fragments were positive for the pestivirus 5'UTR, and the CNS and intestinal tissue fragments were positive for the pestivirus Npro gene. Amplicons with high DNA quantification in the 5'UTR (CNS-cerebral cortex) and Npro (CNS-cerebral cortex and intestine) RT-PCR assays were sequenced. The nucleotide (nt) sequence and phylogenetic analysis of the 5'UTR strain exhibited 93.6 to 99.4%, 85%, 89.4 to 89.9%, 85.1%, and 90.5 to 91.5% nt identity with HoBiPeV strains from clades a, b, c, d, and e, respectively. The Npro amplicons showed 99.7% nt identity to each other and 90.4 to 96.5%, 85.1 to 85.3%, 79.2 to 79.7%, and 85.8 to 86.5% nt identity with HoBiPeV strains from clades a, c, d, and e, respectively. A histopathology revealed neuronal necrosis at the cerebrum, cerebellum, and brain stem. An immunohistochemical assay designed to identify antigens of bovine viral diarrhea virus revealed positive intracytoplasmic immunoreactivity within neurons at the cerebral cortex, cerebrum, cerebellum, and spinal cord. Thus, this report provides information about the first identification of HoBiPeV in tissues of the CNS in a newborn dairy calf with neurological symptoms.

Intrauterine Fetal Demise After Uncomplicated COVID-19: What Can We Learn from the Case?

BACKGROUND: SARS-CoV-2 infection in pregnant women can lead to placental damage and transplacental infection transfer, and intrauterine fetal demise is an unpredictable event. CASE STUDY: A 32-year-old patient in her 38th week of pregnancy reported loss of fetal movements. She overcame mild COVID-19 with positive PCR test 22 days before. A histology of the placenta showed deposition of intervillous fibrinoid, lympho-histiocytic infiltration, scant neutrophils, clumping of villi, and extant infarctions. Immunohistochemistry identified focal SARS-CoV-2 nucleocapsid and spike protein in the syncytiotrophoblast and isolated in situ hybridization of the virus' RNA. Low ACE2 and TMPRSS2 contrasted with strong basigin/CD147 and PDL-1 positivity in the trophoblast. An autopsy of the fetus showed no morphological abnormalities except for lung interstitial infiltrate, with prevalent CD8-positive T-lymphocytes and B-lymphocytes. Immunohistochemistry and in situ hybridization proved the presence of countless dispersed SARS-CoV-2-infected epithelial and endothelial cells in the lung tissue. The potential virus-receptor protein ACE2, TMPRSS2, and CD147 expression was too low to be detected. CONCLUSION: Over three weeks' persistence of trophoblast viral infection lead to extensive intervillous fibrinoid depositions and placental infarctions. High CD147 expression might serve as the dominant receptor for the virus, and PDL-1 could limit maternal immunity in placental tissue virus clearance. The presented case indicates that the SARS-CoV-2 infection-induced changes in the placenta lead to ischemia and consecutive demise of the fetus. The infection of the fetus was without significant impact on its death. This rare complication of pregnancy can appear independently to the severity of COVID-19's clinical course in the pregnant mother.

SARS-CoV-2 Infection in Pregnancy: Clinical Signs, Placental Pathology, and Neonatal Outcome-Implications for Clinical Care.

Introduction: The current COVID-19 pandemic has been associated with high rates of mortality and significant morbidity. Both the risk of infection for pregnant women and the risk of vertical transmission have been evaluated, and the presence of the SARS-CoV-2 virus has been demonstrated both in the placenta and in the amniochorionic membranes. However, the actual effects of this pathogen on pregnancy and on placental morphology are still unclear. Objective: To describe histopathologic findings in the placentas of women with SARS-CoV-2 infection during pregnancy and their correlation with clinical signs and perinatal outcome. Methods: Placental tissues from pregnant women with SARS-CoV-2 infection delivering between March 2020 and February 2021 were analyzed. Results: One hundred six placentas from women with SARS-CoV-2 infection during pregnancy who delivered in Fondazione Policlinico A. Gemelli were examined. Most of them were asymptomatic. All neonates had available test results for SARS-CoV-2 and only one resulted positive. Placental tissues mainly showed signs of maternal vascular malperfusion and of placenta injury in terms of syncytial node increase (96.2%), villar agglutination (77.3%), neointimal hyperplasia (76.4%), excessive fibrin deposition (43.3%), and chorangiosis (35.8%). No significant differences in the frequency of the histopathological lesions were observed according to maternal symptoms. Conclusion: Looking to placental tissues from SARS-CoV-2 positive women at the screening performed close to delivery, placental injuries could be detected without any correlation with fetal and neonatal outcomes. We hypothesize that short latency between SARS-CoV-2 infection and delivery is the main reason for these observations.

Mother-to-Child Transmission of Human T-Cell Leukemia Virus Type 1: Mechanisms and Nutritional Strategies for Prevention.

Approximately 95% of mother-to-child transmission (MTCT) of human T-cell leukemia virus type-1 (HTLV-1) is derived from prolonged breastfeeding, which is a major cause of adult T-cell leukemia (ATL). Exclusive formula feeding (ExFF) is therefore generally used to prevent MTCT. A recent cohort study revealed that 55% of pregnant carriers chose short-term breastfeeding for ≤3 months in Japan. Our meta-analysis showed that there was no significant increase in the risk of MTCT when breastfeeding was carried out for ≤3 months compared with ExFF (pooled relative risk (RR), 0.72; 95% confidence interval (CI), 0.30-1.77), but there was an almost threefold increase in risk when breastfeeding was carried out for up to 6 months (pooled RR, 2.91; 95% CI, 1.69-5.03). Thus, short-term breastfeeding for ≤3 months may be useful in preventing MTCT. Breastmilk is the best nutritional source for infants, and any approach to minimizing MTCT by avoiding or limiting breastfeeding must be balanced against the impact on the child's health and mother-child bonding. To minimize the need for nutritional interventions, it is necessary to identify factors that predispose children born to carrier mothers to MTCT and thereby predict MTCT development with a high degree of accuracy.

Placental Expression of ACE2 and TMPRSS2 in Maternal Severe Acute Respiratory Syndrome Coronavirus 2 Infection: Are Placental Defenses Mediated by Fetal Sex?

BACKGROUND: Expression of angiotensin-converting enzyme 2 (ACE2) and type II transmembrane serine protease (TMPRSS2), host molecules required for viral entry, may underlie sex differences in vulnerability to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We investigated whether placental ACE2 and TMPRSS2 expression vary by fetal sex in the presence of maternal SARS-CoV-2 infection. METHODS: Placental ACE2 and TMPRSS2 expression was quantified by quantitative reverse transcription polymerase chain reaction (RT-PCR) and by Western blot in 68 pregnant women (38 SARS-CoV-2 positive, 30 SARS-CoV-2 negative) delivering at Mass General Brigham from April to June 2020. The impact of fetal sex and maternal SARS-CoV-2 exposure on ACE2 and TMPRSS2 was analyzed by 2-way analysis of variance (ANOVA). RESULTS: Maternal SARS-CoV-2 infection impacted placental TMPRSS2 expression in a sexually dimorphic fashion (2-way ANOVA interaction, P = .002). We observed no impact of fetal sex or maternal SARS-CoV-2 status on ACE2. TMPRSS2 expression was significantly correlated with ACE2 expression in males (Spearman ρ = 0.54, P = .02) but not females (ρ = 0.23, P = .34) exposed to maternal SARS-CoV-2. CONCLUSIONS: Sex differences in placental TMPRSS2 but not ACE2 were observed in the setting of maternal SARS-CoV-2 infection, which may have implications for offspring vulnerability to placental infection.

Transplacental transmission of Theileria annulata in cattle confirmed by molecular techniques.

Theileria annulata (T. annulata) is a tick-borne apicomplexan parasite affecting ruminants and causes severe economic loss. The present paper reports the vertical transmission of T. annulata in a three day old crossbred Jersey calf. Molecular diagnosis of tropical theileriosis was done by PCR, cloning, sequencing and phylogenetic analysis of isolated parasites. Calf showed very low hematocrit value (HCT) (17.82%), red blood cells count (RBC) count (6.9 × 106/µL), and hemoglobin concentration (Hb) (6.6 g/dL). Phylogenetic analysis of Tams 1 gene showed that T. annulata Khorda isolate (MW123091) shared 99.23%, 99.23% and 99.11% nucleotide homology with Puri, India (MN818858), Bahrain (AF214797) and Hyderabad, India (MK034702), respectively. This is the first study in Odisha, India to give an insight into the molecular detection, phylogeny and hematological analysis of T. annulata infected crossbred Jersey calf which got the infection through transplacental transmission.

Possible Vertical Transmission From an Unsuspected SARS-CoV-2-Infected Mother to Her Newborn.

Although the Coronavirus Disease 2019 (COVID-19) has been found to have multiple routes of transmission, limited data exist on whether the vertical transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can occur from asymptomatic infected mothers to their newborns during pregnancy. We report a full-term newborn girl who was found to be positive for COVID-19 at 24 hours of life and subsequently symptomatic with fever, tachycardia, tachypnea, elevated lactate dehydrogenase, and elevated total bilirubin. The newborn was delivered by a mother who was not suspected of having COVID-19 before giving birth, but who developed fever and dyspnea five hours after delivery and was found to be positive for COVID-19. Upon further history collection, the mother reported recent mild nasal congestion in the days prior to delivery. This case highlights that the vertical transmission of COVID-19 to a newborn may occur late during the third trimester from a mother who was not suspected of having the infection. All pregnant women may need to be screened for COVID-19 symptoms, including non-specific symptoms, prior to admission for labor and delivery floors in order to perform diagnostic tests and recommended safety precautions to keep newborns and hospital personnel safe.

Molecular Pathology Analysis of SARS-CoV-2 in Syncytiotrophoblast and Hofbauer Cells in Placenta from a Pregnant Woman and Fetus with COVID-19.

A small number of neonates delivered to women with SARS-CoV-2 infection have been found to become infected through intrauterine transplacental transmission. These cases are associated with a group of unusual placental pathology abnormalities that include chronic histiocytic intervillositis, syncytiotrophoblast necrosis, and positivity of the syncytiotrophoblast for SARS-CoV-2 antigen or RNA. Hofbauer cells constitute a heterogeneous group of immunologically active macrophages that have been involved in transplacental infections that include such viral agents as Zika virus and human immunodeficiency virus. The role of Hofbauer cells in placental infection with SARS-CoV-2 and maternal-fetal transmission is unknown. This study uses molecular pathology techniques to evaluate the placenta from a neonate infected with SARS-CoV-2 via the transplacental route to determine whether Hofbauer cells have evidence of infection. We found that the placenta had chronic histiocytic intervillositis and syncytiotrophoblast necrosis, with the syncytiotrophoblast demonstrating intense positive staining for SARS-CoV-2. Immunohistochemistry using the macrophage marker CD163, SARS-CoV-2 nucleocapsid protein, and double staining for SARS-CoV-2 with RNAscope and anti-CD163 antibody, revealed that no demonstrable virus could be identified within Hofbauer cells, despite these cells closely approaching the basement membrane zone of the infected trophoblast. Unlike some other viruses, there was no evidence from this transmitting placenta for infection of Hofbauer cells with SARS-CoV-2.

Saccharomyces boulardii reduces the vertical transmission of Toxocara canis larvae in mice.

Probiotics have been shown to reduce the intensity of Toxocara canis infection in mice. However, larval transmission of this nematode also occurs via transplacental and transmammary routes. Thus, the aim of this study was to evaluate the effect of the Saccharomyces boulardii probiotic on the vertical transmission of T. canis in Swiss mice. The mice received 107S. boulardii colony-forming units per gram of food. The supplementation began 15 days before mating and was maintained throughout pregnancy and lactation. The animals were inoculated with 300 T. canis embryonated eggs on the 14th day of pregnancy. The presence of larvae was examined in the organs of the females and their offspring. The examined organs included the following: brain, liver, lungs, heart, kidneys, spleen, eye, skeletal muscle (carcass) and mammary glands of lactating females. There was a 42% (P = 0.041) reduction in the number of larvae transmitted to offspring in the group that received probiotic-supplemented food (GI). Additionally, there was a 50% reduction (P = 0.023) in the number of larvae found in the brains of lactating offspring in the GI group. These results reveal the potential of S. boulardii probiotic use as an auxiliary method of controlling visceral toxocariasis.

Disseminated Toxoplasmosis in a Narrow-Ridged Finless Porpoise (Neophocaena asiaeorientalis) with Transplacental Embryonal Transmission.

We describe a case of systemic toxoplasmosis in a female adult narrow-ridged finless porpoise (Neophocaena asiaeorientalis) found in May 2018 inside a gillnet set in the Ariake Sound, southern Japan. The main lesions observed were lymphoplasmacytic and focally necrotizing encephalitis, necrotizing to granulomatous adrenalitis, myocarditis, and inflammation in the intestinal wall, associated with protozoal tissue cysts and tachyzoites. Additionally, the individual had a 5.6 mm (crown-rump length) early-stage embryo in the left uterine horn, which had multifocal necrotizing lesions with intralesional tissue cysts and tachyzoites in the parenchyma. Immunohistochemistry and PCR and sequencing of the internal transcribed spacer 1 region confirmed a Toxoplasma gondii infection. Further genotyping revealed an atypical type II genotype with a type I pattern for the Apico locus. Narrow-ridged finless porpoises are an endangered coastal species already facing various anthropogenic threats. Toxoplasmosis, especially with its ability to transmit to an early-stage embryo, should be considered an emerging threat to this vulnerable species.