Recent decline in hepatitis E virus prevalence among wild boars in Japan: Probably due to countermeasures implemented in response to outbreaks of classical swine fever virus infection.

Previous studies have emphasized the necessity of surveillance and control measures for hepatitis E virus (HEV) infection in wild boars, an important reservoir of HEV. To assess the current situation of HEV infection in wild boars in Japan, this study investigated the prevalence and genetic diversity of HEV among wild boars captured in 16 prefectures of Japan during 2018-2023. Serum samples from 968 wild boars were examined for anti-HEV IgG antibodies and HEV RNA. The prevalence of anti-HEV IgG varied geographically from 0 % to 35.0 %. HEV RNA was detected in 3.6 % of boars, with prevalence varying by prefecture from 0 % to 22.2 %. Genotype 3 was the most prevalent genotype (91.9 %), followed by genotype 4 (5.4 %), with one strain closely related to genotype 6. The prevalence of HEV infection among wild boars decreased from 2018/2019 to 2022/2023 with significant declines in levels of anti-HEV IgG antibodies (14.5 % vs. 6.2 %, P < 0.0001) and HEV RNA (7.6 % vs. 1.5 %, P < 0.0001). Regional analysis showed varying trends, with no HEV RNA-positive boars found in several regions in recent years. A plausible factor contributing to the decline in HEV infection is the application of countermeasures, including installing fences to prevent intrusion into pig farms, implemented in response to the emergence of classical swine fever virus (CSFV) infection in wild boars and domestic pigs, with incidents reported annually since 2018. Further investigation is warranted to explore the association between countermeasures to CSFV infection and the decrease in HEV infection among wild boars.

Puppies as the primary causal animal for human rabies cases: three-year prospective study of human rabies in the Philippines.

Introduction: While rabies remains a global concern, detailed studies on human rabies, particularly regarding causal animals and the reasons for not receiving postexposure prophylaxis (PEP), are lacking. Methods: We conducted a 3-year prospective study (October 2019-September 2022) at the Philippines' largest rabies referral center. We interviewed patients with suspected rabies and their families. We used LN34 qRT-PCR and rapid fluorescent focus inhibition test on saliva samples. We also compared our findings with two retrospective studies at the same hospital. Results: We enrolled 151 patients, including 131 with potential rabies exposure. Similar to retrospective studies, the participants were predominantly males (75.5%), adults (76.8%), low-income individuals (91.4%), and rural dwellers (62.3%). The causal animals were mainly dogs (97.0%), with similar incubation periods, clinical symptoms, and a high proportion not receiving vaccines or immunoglobulins (93.2%). Most causal animals were owned by either the patients' households or their neighbors (60.2%), with a significant proportion being puppies (58.8%). Most patients had knowledge of rabies; however, reasons for not seeking PEP included misconceptions about minor bites not causing rabies (51.3%), beliefs in traditional healers (33.9%), and economic constraints (22.6%). Despite completing the WHO regimen, two PEP failures were observed. LN34 qRT-PCR detected 98 positive cases (sensitivity, 64.9%; 95% CI 56.7-72.5). These strains belong to the Southeast Asia 4 subclade. Discussion: In conclusion, this study highlights the role of puppies as primary causal animals and the presence of misconceptions that preclude patients from acquiring PEP.

Bangladesh records persistently increased number of dengue deaths in recent years: Dissecting the shortcomings and means to resolve.

Objectives: Dengue, a life-threatening disease caused by the mosquito-borne dengue virus, has become a severe problem in recent years in Bangladesh, a South Asian country. In this study, we have critically analyzed the factors contributing to the escalation of the dengue burden in recent years in Bangladesh and discussed the strategies for effective control. Design: This retrospective observational study analyzed the dengue data collected from the five most dengue-affected countries (Bangladesh, Brazil, Mexico, Peru, and the Philippines) from 2019 to 2023. Results: An increased number of dengue-related deaths has been recorded in Bangladesh since 2021. The year 2023 has witnessed a record high dengue-related deaths in Bangladesh, with cumulative deaths for the year surpassing all totals of the previous 23 years (2000-2022: 853 deaths vs 2023: 1705 deaths). Comparing the epidemiologic data of major dengue-endemic countries over the last 5 years, Bangladesh recorded higher dengue fatality rates consecutively for 3 years. Besides the environmental and viral host factors, which are also applicable to many other dengue-endemic countries, there is concern about the failures and mismanagement of authorities to manage dengue patients properly. Conclusion: This study provided evidence that Bangladesh recorded higher dengue fatality rates in recent years. By implementing multi-pronged proactive approaches that can ensure proper prevention programs and appropriate patient management, Bangladesh or similar other countries can significantly reduce the current dengue burden and the associated deaths.

Rapid Detection of Severe Fever with Thrombocytopenia Syndrome Virus in the Acute Phase of Infection by Direct Real-Time Reverse Transcription without RNA Extraction.

No specific treatment has been developed for severe fever with thrombocytopenia syndrome (SFTS). However, the prognosis can improve with early plasma exchange. Therefore, rapid and accurate detection of SFTS virus is important for diagnosis and prognosis. Direct real-time reverse transcription polymerase chain reaction (RT-PCR) testing is easier and more time-efficient than conventional real-time RT-PCR. Our study compared direct real-time RT-PCR efficiency without the RNA extraction and purification of conventional real-time RT-PCR. Samples were collected from 18 patients with SFTS and five without SFTS. A strong correlation (r = 0.774, 95% CI: 0.652-0.857, P <0.01) was found between conventional and direct real-time RT-PCR assays. Direct real-time RT-PCR showed 84.4% sensitivity and 92.0% specificity for viral detection. Direct real-time RT-PCR is an effective diagnostic tool for patients with acute phase SFTS, but further optimization is required for viral detection.

Intractable Nocardial mycetoma with possible colonisation by Candida species.

A Japanese male in his 30s with no underlying medical condition presented with painless nodules after being bitten by a dog during a stay in Bali, Indonesia, 7 years earlier. He was referred to our department with multiple ulcers, nodules, and masses on the right leg. The final diagnosis was mycetoma caused by Nocardia vulneris, which may have been exacerbated by colonization of Candida parapsilosis and C. tropicalis as these yeasts were isolated by culture from the tissue. Treatment with minocycline hydrochloride and sulfamethoxazole trimethoprim showed partial efficacy, but the addition of posaconazole achieved significant efficacy. This suggests that the surmised coexistence of pathogenic yeasts of lower virulency may have made mycetoma in this case intractable.

Cytocidal Effect of Irradiation on Gastric Cancer Cells Infected with a Recombinant Mammalian Orthoreovirus Expressing a Membrane-Targeted KillerRed.

The outcomes of unresectable gastric cancer (GC) are unfavorable even with chemotherapy; therefore, a new treatment modality is required. The combination of an oncolytic virus and photodynamic therapy can be one of the promising modalities to overcome this. Mammalian orthoreovirus (MRV) is an oncolytic virus that has been used in clinical trials for several cancers. In this study, we developed and evaluated a recombinant MRV strain type 3 Dearing (T3D) that expresses membrane-targeting KillerRed (KRmem), a phototoxic fluorescent protein that produces cytotoxic reactive oxygen species upon light irradiation. KRmem was fused in-frame to the 3' end of the σ2 viral gene in the S2 segment using a 2A peptide linker, enabling the expression of multiple proteins from a single transcript. RNA electrophoresis, Western blotting, and immunofluorescence analyses confirmed functional insertion of KRmem into the recombinant virus. The growth activity of the recombinant virus was comparable to that of the wild-type MRV in a cultured cell line. The recombinant virus infected two GC cell lines (MKN45P and MKN7), and a significant cytocidal effect was observed in MKN45P cells infected with the recombinant virus after light irradiation. Thus, recombinant MRV-expressing KRmem has the potential to serve as a novel treatment tool for GC.

Thyroid abscess associated with thyrotoxicosis caused by Yersinia enterocolitica subsp. palearctica in a patient with follicular adenoma of the thyroid gland.

BACKGROUND: Yersinia enterocolitica is a gram-negative zoonotic bacterial pathogen that is typically transmitted via the fecal-oral route. The most common clinical manifestation of a Y. enterocolitica infection is self-limited gastroenteritis. Although various extraintestinal manifestations of Y. enterocolitica infection have been reported, there are no reports of thyroid abscesses. CASE PRESENTATION: An 89-year-old Japanese man with follicular adenoma of the left thyroid gland was admitted to our hospital with a 2-day history of fever and left neck pain. Laboratory tests revealed low levels of thyroid stimulating hormone and elevated levels of free thyroxine 4. Contrast-enhanced computed tomography showed low-attenuation areas with peripheral enhancement in the left thyroid gland. He was diagnosed with thyroid abscess and thyrotoxicosis, and treatment with intravenous piperacillin-tazobactam was initiated after collecting blood, drainage fluid, and stool samples. The isolated Gram-negative rod bacteria from blood and drainage fluid cultures was confirmed to be Y. enterocolitica. He was diagnosed with thyroid abscess and thyrotoxicosis due to be Y. enterocolitica subsp. palearctica. The piperacillin-tazobactam was replaced with levofloxacin. CONCLUSION: We report a novel case of a thyroid abscess associated with thyrotoxicosis caused by Y. enterocolitica subsp. palearctica in a patient with a follicular thyroid adenoma.

Neurotoxic stimulation alters prosaposin levels in the salivary systems of rats.

Prosaposin (PSAP), a potent neurotrophic factor, is found in neuronal and non-neuronal tissues and various biological fluids. Neuropathological conditions often alter PSAP production in neural tissues. However, little is known about its alterations in non-neural tissues, particularly in the salivary glands, which are natural reservoirs of various neurotrophic factors. In this study, we explored whether neurotoxic stimulation by kainic acid (KA), a glutamate analog, altered PSAP levels in the salivary system of rats. The results revealed that KA injection did not alter total saliva production. However, KA-induced neurotoxic stimulation significantly increased the PSAP level in the secreted saliva but decreased it in the serum. In addition, KA-induced elevated immunoreactivities of PSAP and its receptors have been observed in the granular convoluted tubule (GCT) cells of the submandibular gland (SMG), a major salivary secretory organ. Indeed, a large number of PSAP-expressing immunogold particles were observed in the secretory granules of the SMG. Furthermore, KA-induced overexpression of PSAP was co-localized with secretogranin in secretory acini (mostly in GCT cells) and the ductal system of the SMG, suggesting the release of excess PSAP from the salivary glands into the oral cavity. In conclusion, the salivary system produces more PSAP during neurotoxic conditions, which may play a protective role in maintaining the secretory function of the salivary glands and may work in distant organs.

Seroprevalence kinetics of SARS-CoV-2 antibodies in pediatric patients visiting a hospital during COVID-19 pandemic in Japan.

Children infected with SARS-CoV-2 are often asymptomatic or have mild symptoms. The studies on the seroprevalence kinetics of SARS-CoV-2 antibodies in children are limited. We conducted a cross-sectional survey of the positive rate of the SARS-CoV-2 IgG in pediatric patients without suspected COVID-19 infection between January 2007 and March 2022. We defined the serum samples from the pre-pandemic and pandemic groups (1st-6th waves). Totally, 2557 samples were collected and no samples from the pre-pandemic group or the 1st-4th waves were positive for IgG. There were 4/661 and 16/373 positives at the 5th and 6th waves, respectively. At the 5th wave, the prevalence of IgG was 1.3% in children aged 1-4 years. At the 6th wave, in children <1 year of age, the prevalence was 4.0%, and 2.4%, 5.3%, 5.2% and 10% in age groups 1-4, 5-9, 10-14 and 15-18 years, respectively. In conclusions, the pre-pandemic samples were negative, and the IgG positivity increased during the later period of the pandemic.

Evaluation of lateral flow devices for postmortem rabies diagnosis in animals in the Philippines: a multicenter study.

Expansion of the use of lateral flow devices (LFD) for animal rabies diagnosis can help mitigate the widespread underreporting of rabies. However, this has been hindered by the limited number and small sample size of previous studies. To overcome this limitation, we conducted a multicenter study with a larger sample size to assess the diagnostic accuracy of the ADTEC LFD for postmortem rabies diagnosis in animals. Thirteen governmental animal diagnostic laboratories in the Philippines were involved in this study, and 791 animals suspected of having rabies were tested using both the direct fluorescence antibody test (DFAT) and ADTEC LFD between August 2021 and October 2022. The LFD demonstrated a sensitivity of 96.3% [95% confidence interval (CI): 94.1%-97.9%] and a specificity of 99.7% (95% CI: 98.4%-100%). Notably, false-negative results were more likely to occur in laboratories with lower annual processing volumes of rabies samples in the previous years (adjusted odds ratio 4.97, 95% CI: 1.49-16.53). In this multicenter study, the high sensitivity and specificity of the LFD for the diagnosis of animal rabies, compared to that of the DFAT, was demonstrated, yet concerns regarding false-negative results remain. In areas with limited experience in processing rabies samples, it is essential to provide comprehensive training and careful attention during implementation.

Bacillus subtilis Bacteremia from Gastrointestinal Perforation after Natto Ingestion, Japan.

We report a case of Bacillus subtilis variant natto bacteremia from a gastrointestinal perforation in a patient who ingested natto. Genotypic methods showed the bacteria in a blood sample and the ingested natto were the same strains. Older or immunocompromised patients could be at risk for bacteremia from ingesting natto.

Perception of overseas experiences among medical students in Japan: a national online survey.

BACKGROUND: Data on the perceptions of medical students on international experience in non-English-speaking high-income countries (HICs) are very limited. This study aimed to assess the perceptions of medical students in Japan toward overseas experience while in school and post-graduation, as well as to characterize the support they require to pursue their profession in international settings. METHODS: A cross-sectional national survey was administered online between September 16, 2020, and October 8, 2020. Participants were recruited from 69 medical schools using snowball sampling through acquaintances and social media platforms. The survey results were analyzed by two researchers. RESULTS: A total of 548 students from 59 medical schools responded to the survey. Among them, 381 respondents (69%) expressed interest in working abroad, while only 40% seriously considered it. The majority of students responded that they would like to pursue clinical training abroad for a short term or while they were medical students (54%) or during a residency/fellowship (53%). The most popular regions among the respondents for future international experiences were North America and Europe. Finally, the most reported reasons for hesitation to work abroad were language barriers (70%), followed by lack of clarity regarding career options after working abroad (67%), difficulties obtaining medical licensure abroad (62%), and the lack of role models (42%). CONCLUSIONS: Although nearly 70% of participants reported a high interest in working overseas, various barriers to working abroad were identified. Our findings identified key problem areas that could be targeted when promoting international experiences for medical students in Japan.

Massive and Lengthy Clonal Nosocomial Expansion of Mycobacterium abscessus subsp. massiliense among Patients Who Are Ventilator Dependent without Cystic Fibrosis.

Nontuberculous mycobacterial infections are generally believed to be independently acquired from the environment. Although person-to-person transmission of nontuberculous mycobacteria, especially Mycobacterium abscessus subsp. massiliense, is a serious concern among individuals with cystic fibrosis (CF), evidence of its spread among patients without CF has never been established. We unexpectedly found a number of M. abscessus subsp. massiliense cases among patients without CF in a hospital. This study aimed to define the mechanism of M. abscessus subsp. massiliense infection among patients who were ventilator dependent and without CF who had progressive neurodegenerative diseases in our long-term care wards from 2014 to 2018 during suspected nosocomial outbreaks. We conducted whole-genome sequencing of M. abscessus subsp. massiliense isolates from 52 patients and environmental samples. Potential opportunities for in-hospital transmission were analyzed using epidemiological data. M. abscessus subsp. massiliense was isolated from one air sample obtained near a patient without CF who was colonized with M. abscessus subsp. massiliense but not from other potential sources. Phylogenetic analysis of the strains from these patients and the environmental isolate revealed clonal expansion of near-identical M. abscessus subsp. massiliense isolates, with the isolates generally differing by fewer than 22 single nucleotide polymorphisms (SNPs). Approximately half of the isolates differed by fewer than nine SNPs, indicating interpatient transmission. Whole-genome sequencing revealed a potential nosocomial outbreak among patients who were ventilator dependent and without CF. IMPORTANCE The isolation of M. abscessus subsp. massiliense from the air, but not from environmental fluid samples, may suggest airborne transmission. This was the first report to demonstrate person-to-person transmission of M. abscessus subsp. massiliense, even among patients without CF. M. abscessus subsp. massiliense may spread among patients who are ventilator dependent without CF through direct or indirect in-hospital transmission. The current infection control measures should address potential transmission among patients without CF, particularly in facilities that treat patients who are ventilator dependent and patients with preexisting chronic pulmonary diseases, such as CF.

Administration of prosaposin-derived neurotrophic factor to neural tube defects facilitates regeneration and restores neurological functions.

Neural tube defects (NTDs) cause fetal and pediatric deaths or lifelong neurological disabilities. No effective treatment is currently available for NTDs. We attempted to elucidate the pathogenesis of NTDs and propose a therapeutic strategy. Intra-amniotic treatment with prosaposin-derived 18-mer peptide (PS18) protected the spinal cord from secondary damage and rescued neurological function in an established chicken model of spina bifida aperta (SBA), the severe type of NTDs. PS18 promoted the formation of a neuroectodermal covering over the defective neural tube within 24-h after treatment, enhanced the regeneration/restoration process, and decreased apoptotic activity in the developing spinal cord. PS18 reduced the SBA wound and almost completely formed the spinal cord. SBA chicks that received PS18 exhibited relatively normal walking and sensorimotor responses, and reduced pain-associated behavior in postnatal life. In conclusion, PS18 is a promising therapeutic agent for NTDs and may be useful for treating other types of spinal cord injuries.

Evaluation of a real-time mobile PCR device (PCR 1100) for the detection of the rabies gene in field samples.

BACKGROUND: The Philippines is ranked among the top countries with 200-300 annual deaths due to rabies. Most human rabies cases have been reported in remote areas, where dog surveillance is inadequate. Therefore, a strategy to effectively improve surveillance in remote areas will increase the number of detections. Detecting pathogens using portable real-time reverse transcription-polymerase chain reaction (RT-PCR) has the potential to be accepted in these areas. Thus, we aimed to develop an assay to detect the rabies virus (RABV) genome by combining the robust primer system LN34 with the PicoGene PCR1100 portable rapid instrument targeting RABV RNA (PCR1100 assay). METHODS: Procedures were optimised using an LN34 primer/probe set, KAPA3G Plant PCR Kit (KAPA Biosystems), FastGene Scriptase II (NIPPON Genetics), and an artificial positive control RNA. RESULTS: Positive control RNA showed an analytical limit of detection of 10 copies/µL without false positivity, generating results in approximately 32 min. Compared to dFAT or RT-qPCR using field samples, the sensitivity and specificity of the PCR1100 assay were 100%, and even lower copy numbers (approximately 10 copies/µL) were detected. CONCLUSIONS: This study demonstrated that the developed assay can detect rabies RNA in field samples. Because dog-mediated rabies is endemic in remote areas, the rapidity, mobility, and practicality of the PCR1100 assay as well as the high sensitivity of the LN34 system make it an ideal tool for the confirmation of rabies in these areas.

Molecular Analysis of Rabies Virus Using RNA Extracted from Used Lateral Flow Devices.

Molecular analysis of rabies virus can provide accurate diagnosis and information on its genetic diversity. The transportation of rabies brain samples from remote areas to a central laboratory is challenging owing to biohazard risks and decomposability. We investigated the utility of used lateral flow devices (LFDs) for subsequent molecular analysis and assessed the necessary storage temperatures. Using RNA extracted from used LFD strips, we performed conventional reverse transcription-PCR (RT-PCR) using an LN34 primer set to amplify short fragments (165 bp) for rabies virus detection and the P1-304 primer set to amplify long fragments of the entire N gene amplicon (1,506 bp) for phylogenetic analysis. Among 71 used LFDs stored in a refrigerator and 64 used LFDs stored at room temperature, the LN34 assay showed high sensitivities (96.2% and 100%, respectively) for the diagnosis of rabies, regardless of the storage temperature. A significant reduction in the sensitivity of rabies diagnosis was observed when using the P1-304 primer set for used LFDs stored at room temperature compared to those stored at refrigeration temperature (20.9% versus 100%; P < 0.05). Subsequent sequencing and phylogenetic analysis were successfully performed using the amplicons generated by the P1-304 RT-PCR assays. Used LFDs are thus promising resources for rabies virus RNA detection and sequence analysis. Virus detection via RT-PCR, amplifying a short fragment, was possible regardless of the storage temperature of the used LFDs. However, refrigerated storage is recommended for RT-PCR amplification of long fragments for phylogenetic analysis.

Implications of the antiviral drug favipiravir on rabies immunoglobulin for post-exposure prophylaxis of rabies in mice model with category III-like exposures.

Rabies is a fatal zoonotic disease caused by the rabies virus (RABV), with almost 100% mortality if proper post-exposure prophylaxis (PEP), consisting of rabies immunoglobulin (RIG) and rabies vaccine, is not applied in a timely manner. However, this is challenged by the limited availability of RIG, especially in resource-constrained countries. In this study, we assessed the scope of the antiviral drug favipiravir to treat rabies-infected mice as an alternative to RIG. Category III-like wounds were induced in RABV-challenged mice treated with favipiravir instead of RIG in the PEP regimen. The use of favipiravir followed by rabies vaccine provided complete protection against rabies-related death in 100% of mice, even after RABV propagated to the central nervous system during infection. Additionally, the virus-neutralizing antibody titer in the favipiravir and vaccine group was significantly higher than that of the RIG and vaccine recipients. The use of favipiravir with rabies vaccine seemingly prevents fatal outcomes and even rescues the cases that already express clinical symptoms. A clinical trial of this approach is warranted, especially in countries with low RIG availability.

Recent Dengue Infection in Bangladesh: A Seasonal Endemic Progressing to Year-long Serious Health Concern.

Dengue represents one of the most dangerous mosquito-borne viral diseases. Although the disease has been prevalent around the globe over the centuries, recent outbreaks of dengue have devasted the healthcare delivery system of many countries. Being a global infection, dengue virus (DENV) is endemically present mainly in Latin America and Caribbean countries as well as countries in South Asia. The recent outbreak of DENV infection has indicated an exceptional outbreak of DENV in some countries in South Asia. There has been a serious endemic of DENV during 2019. After a heterogeneous pause, another severe outbreak of DENV was reported in some Asian countries in 2023. Among the Asian countries, Bangladesh has reported an acute upsurge of DENV infection in 2023 with record numbers of fatalities. However, this pattern of DENV has not been detected in neighbors of Bangladesh, such as India or other countries in Southeast Asia. This provides an emergent task of dissecting the present DENV infection in Bangladesh from different angles to get insights for future containment of the DENV infection, not only in Bangladesh but also in other DENV endemic areas or DENV-native areas. How to cite this article: Akbar SMF, Khan S, Mahtab M, et al. Recent Dengue Infection in Bangladesh: A Seasonal Endemic Progressing to Year-long Serious Health Concern. Euroasian J Hepato-Gastroenterol 2023;13(2):145-151.

IMiD/CELMoD-induced growth suppression of adult T-cell leukemia/lymphoma cells via cereblon through downregulation of target proteins and their downstream effectors.

Adult T-cell leukemia/lymphoma (ATL) is an aggressive T-cell neoplasia associated with human T-cell leukemia virus type 1 (HTLV-1) infection and has an extremely poor prognosis. Lenalidomide (LEN; a second-generation immunomodulatory drug [IMiD]) has been employed as an additional therapeutic option for ATL since 2017, but its mechanism of action has not been fully proven, and recent studies reported emerging concerns about the development of second primary malignancies in patients treated with long-term IMiD therapy. Our purpose in this study was to elucidate the IMiD-mediated anti-ATL mechanisms. Thirteen ATL-related cell lines were divided into LEN-sensitive or LEN-resistant groups. CRBN knockdown (KD) led to a loss of LEN efficacy and IKZF2-KD-induced LEN efficacy in resistant cells. DNA microarray analysis demonstrated distinct transcriptional alteration after LEN treatment between LEN-sensitive and LEN-resistant ATL cell lines. Oral treatment of LEN for ATL cell-transplanted severe combined immunodeficiency (SCID) mice also indicated clear suppressive effects on tumor growth. Finally, a novel cereblon modulator (CELMoD), iberdomide (IBE), exhibited a broader and deeper spectrum of growth suppression to ATL cells with efficient IKZF2 degradation, which was not observed in other IMiD treatments. Based on these findings, our study strongly supports the novel therapeutic advantages of IBE against aggressive and relapsed ATL.

Histopathologically TMA-like distribution of multiple organ thromboses following the initial dose of the BNT162b2 mRNA vaccine (Comirnaty, Pfizer/BioNTech): an autopsy case report.

BACKGROUND: Coronavirus disease 2019 (COVID-19) has spread worldwide. Vaccination is now recommended as one of the effective countermeasures to control the pandemic or prevent the worsening of symptoms. However, its adverse effects have been attracting attention. Here, we report an autopsy case of multiple thromboses after receiving the first dose of the BNT162b2 mRNA vaccine (Comirnaty, Pfizer/BioNTech) in an elderly woman. CASE PRESENTATION: A 72-year-old woman with a history of diffuse large B-cell lymphoma in the stomach and hyperthyroidism received the first dose of the BNT162b2 mRNA vaccine and died 2 days later. The autopsy revealed multiple microthrombi in the heart, brain, liver, kidneys, and adrenal glands. The thrombi were CD61 and CD42b positive and were located in the blood vessels primarily in the pericardial aspect of the myocardium and subcapsular region of the adrenal glands; their diameters were approximately 5-40 µm. Macroscopically, a characteristic myocardial haemorrhage was observed, and the histopathology of the characteristic thrombus distribution, which differed from that of haemolytic uraemic syndrome and disseminated intravascular coagulation, suggested that the underlying pathophysiology may have been similar to that of thrombotic microangiopathy (TMA). CONCLUSION: This is the first report on a post-mortem case of multiple thromboses after the BNT162b2 mRNA vaccine. The component thrombus and characteristic distribution of the thrombi were similar to those of TMA, which differs completely from haemolytic uraemic syndrome or disseminated intravascular coagulation, after vaccination. Although rare, it is important to consider that fatal adverse reactions may occur after vaccination and that it is vital to conduct careful follow-up.