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Loiasis is a parasitic infection transmitted by a vector, specifically through the bites of Chrysops genus tabanid flies. It is often associated with marked and persistent eosinophilia in affected individuals. We report the case of a 28-year-old Cameroonian male patient. His medical history includes an episode of malaria treated on an outpatient basis. As part of a diving internship in Morocco, the young serviceman underwent a medical fitness examination at the Medical Expertise Center for Aircrew Personnel of the Mohamed V Military Hospital, which included a biological assessment. This revealed a mildly elevated bilirubin level, lactate dehydrogenase activity at the upper limit of normal and eosinophilia at 1500 µl^-1, without anaemia or thrombocytopaenia. A blood smear was prepared and stained with May-Grünwald Giemsa, revealing the presence of several small worms, with an appearance consistent with Loa loa microfilariae. This case of L. loa, identified in the haematology laboratory, is one of the rare diagnoses in Morocco. Therefore, biologists need to remain vigilant and carry out a thorough analysis of the blood count and blood smear.

Introduction. Malaria remains a significant global health concern, particularly in travellers returning from endemic regions. Haematological abnormalities are often associated with malaria and can serve as diagnostic indicators, especially when clinical symptoms are nonspecific. Objective. This study aims to identify the most relevant haematological parameters for diagnosing malaria in travellers returning from endemic areas, who sought care at the Mohamed V Military Instruction Hospital in Rabat. Methods. We conducted a retrospective comparative study involving 829 patients who returned from malaria-endemic regions between January 2017 and December 2023. Data collected included demographic information, parasitological test results and comprehensive haematological profiles. Statistical analysis was performed to determine the sensitivity and specificity of various haematological parameters in diagnosing malaria. Results. Thrombocytopenia, lymphocytopenia and anaemia were the most significant haematological abnormalities associated with malaria. Thrombocytopenia, defined as a platelet count below 150×10³ µl^-1, demonstrated a sensitivity of 75.91% and a specificity of 84.11%. Lymphocytopenia, with a threshold of less than 1.5×10³ µl^-1, showed a sensitivity of 69.47% and a specificity of 78.39%. Anaemia, defined by haemoglobin levels below 13 g dl^-1 in men and 12 g dl^-1 in women, also significantly correlated with malaria diagnosis. Discussion. This study highlights the significance of haematological abnormalities as key diagnostic markers for imported malaria cases. By analysing retrospective data, we observed that these abnormalities, especially thrombocytopenia and anaemia, are common amongst returning travellers with confirmed malaria. These findings suggest that clinicians can use such markers as a valuable tool for early malaria diagnosis, potentially improving patient outcomes. Additionally, the study reinforces the need for heightened awareness amongst healthcare providers in non-endemic regions regarding the presentation of malaria in travellers. Conclusion. Haematological parameters such as thrombocytopenia, lymphocytopenia and anaemia are valuable diagnostic tools for malaria in returning travellers. These findings suggest that these parameters should be integrated into diagnostic protocols to improve the accuracy and timeliness of malaria diagnosis, particularly in clinical settings with limited access to advanced diagnostic tools.

Serratia marcescens (S. marcescens) is a Gram-negative rod-shaped bacterium belonging to the Enterobacteriaceae family, commonly found in various environments. This opportunistic pathogen can cause urinary tract infections, respiratory infections and septicaemia, but endocarditis is particularly rare and concerning due to its rapid and devastating progression. We report the first documented case worldwide of infective endocarditis (IE) caused by S. marcescens producing NDM-type carbapenemase, and the second reported case of S. marcescens endocarditis in a preterm infant. The patient was a preterm male infant born at 34 weeks of gestation, from a triplet pregnancy, admitted to the neonatal intensive care unit on day 2 of life for respiratory distress. The mother, aged 39, had undiagnosed gestational diabetes. Premature rupture of membranes had occurred 10 days before delivery, necessitating prophylactic treatment with amoxicillin. On day 4 of life, the newborn developed a fever with elevated C-reactive protein (CRP) levels and leucocytosis, leading to antibiotic therapy with colistin, imipenem and amikacin. Blood cultures revealed the presence of carbapenemase-producing S. marcescens sensitive to fluoroquinolones. A cardiac ultrasound showed a vegetation on the mitral valve, confirming the diagnosis of IE. Despite intensive treatment, the newborn died on day 16 of life due to septic shock. This rare case of endocarditis caused by S. marcescens highlights the severity of this infection in preterm infants. Treatment relies on appropriate antibiotic therapy. Prevention requires strict hygiene measures. Further research is needed to establish optimal therapeutic recommendations.

Here, we report the draft genome sequences of four Bradyrhizobium spp. isolates obtained from root nodules of the native legumes Pentaclethra macroloba, Chamaecrista nictitans, Erythrina fusca and Zygia engelsingii in tropical forests of Costa Rica. Genomes ranged from 8.6 to 9.8 Mb with GC contents between 62.8% and 63.8%. Phylogenomic analysis, along with average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) comparisons, confirmed that these isolates represent potential new species. ANI values ranged from 88.3% to 90.3%, and dDDH values from 28.8% to 41.8%, compared with their closest Bradyrhizobium species. Functional annotation revealed some genes related to nitrogen fixation (nifA, nifB, nifH) and nodulation capacity (nodB, nodC, nodJ). These results provide insights into the diversity and symbiotic capabilities of Bradyrhizobium in tropical ecosystems.

An outbreak of Zika fever occurred in Thiruvananthapuram City, Kerala, India, during 2021. At the request of the Kerala state health administration, we investigated the same, towards proposing requisite containment strategies for the disease outbreak. Epidemiological investigations indicated a clustering pattern of Zika fever cases with the presumed index case from a multi-speciality hospital in the city. Preliminary reports on the same had been already reported elsewhere during 2021. Further, entomological surveys carried out evinced the predominant mosquito species in the city, viz. Aedes albopictus (65.55%), Aedes aegypti (22.0%) and Aedes vittatus (12.0%) were naturally infected with Zika virus (ZIKV), the minimum infection rates being 17.9, 7.8 and 3.6, respectively. Also, trans-ovarian transmission was recorded in both Ae. aegypti and Ae. albopictus. This is the first report on the detection of ZIKV from Ae. albopictus in India. Analysis of phylogenetically informative genes of the ZIKV genome indicated the emergence of a distinct lineage of the Asian strain of virus, with five unique non-synonymous mutations, viz. 'A22T' and 'I160M' (pre-membrane) and 'D348N', 'T470A' and 'V473L' (envelope), that were involved in the outbreak. The altered gene expression pattern and evolutionary implications of these unique mutations remain to be investigated. Genetic analysis of the virus isolates from this and other investigations carried out on sporadic outbreaks of ZIKV in the country subsequently indicated that ZIKV is re-emerging as a distinct genetic lineage in India. These findings and other recent reports on ZIKV outbreaks warrant an urgent need for a systematic countrywide surveillance strategy, towards the prevention/preparedness/containment of a massive outbreak of this emerging neurovirulent arboviral disease.

Over the past three decades, molecular epidemiological studies have provided new opportunities to investigate the transmission dynamics of Mycobacterium tuberculosis. In most studies, a sizable fraction of individuals with notified tuberculosis cannot be included, either because they do not have culture-positive disease (and thus do not have specimens available for molecular typing) or because resources for conducting sequencing are limited. A recent study introduced a regression-based approach for inferring the membership of unsequenced tuberculosis cases in transmission clusters based on host demographic and epidemiological data. This method was able to identify the most likely cluster to which an unsequenced strain belonged with an accuracy of 35%, although this was in a low-burden setting where a large fraction of cases occurred among foreign-born migrants. Here, we apply a similar model to M. tuberculosis whole-genome sequencing data from the Republic of Moldova, a setting of relatively high local transmission. Using a maximum cluster span of ~40 single nucleotide polymorphisms (SNPs) and a cluster size cutoff of n≥10, we could best predict the specific cluster to which each clustered case was most likely to be a member with an accuracy of 17.2 %. In sensitivity analyses, we found that a more restrictive (~20 SNPs threshold) or permissive (~80 SNPs) threshold did not improve performance. We found that increasing the minimum cluster size improved prediction accuracy. These findings highlight the challenges of transmission inference in high-burden settings like Moldova.

[This corrects the article DOI: 10.1099/acmi.0.000995.v3.].

A 50-year-old Romanian gentleman presented with fever, myalgia and 30 kg weight loss. He was treated for syphilis after acquiring it 16 years ago. On examination, there was a pansystolic murmur in the axilla, and the patient had an ataxic gait. Blood tests showed raised inflammatory markers. However, standard investigations for infective endocarditis, including multiple blood cultures, serological titres for fastidious organisms and antibody tests were negative. A computed tomography (CT) of the chest, abdomen and pelvis demonstrated hepatosplenomegaly with multiple splenic infarcts. A magnetic resonance imaging (MRI) of the head with contrast showed multiple punctate enhancement in the bilateral hemispheres with leptomeningeal enhancement. Transthoracic echocardiogram demonstrated a large vegetation leading to severe mitral regurgitation. Serum treponemal antibodies were positive; Treponema pallidum particle agglutination (TPPA) was positive at 1 : 1280, and rapid plasma reagin (RPR) 1 : 4 treponemal IgM was negative; lumbar puncture syphilis serology was negative. The patient was treated with an extensive period of intravenous antibiotics, in addition to a prosthetic metallic valve replacement, where unusual ragged calcified valvular tissue was observed. Tertiary syphilis is a difficult diagnosis to confirm, since it can often be indolent and occur in areas of the body where it may go unnoticed. In our case, a diagnosis of probable syphilitic endocarditis was made from a combination of the history, an initial increase in the size of the lesion following antibiotic therapy and observation of likely gumma on the mitral valve during surgery. In such cases, surgery in addition to optimal antimicrobial therapy is necessary for effective treatment. This case adds to the current literature that treatment with penicillin is likely inadequate to prevent late complications.

Tuberculosis (TB) remains one of the world's leading causes of morbidity and mortality. It occurs in both pulmonary and extra-pulmonary forms. Primary iliac bone TB remains a rare clinical entity, even in endemic areas. The diagnosis of the disease can be challenging due to its similarity to other bone diseases. We report a rare case of primary iliac bone TB in a 63-year-old patient who was on peritoneal dialysis and had a medical history of hypertension and type II diabetes, which was complicated by diabetic retinopathy and diabetic kidney disease. Magnetic resonance imaging revealed osteomyelitis in the iliac bone, while real-time polymerase chain reaction using the GeneXpert^® system on a gluteal collection sample confirmed the diagnosis of TB. The integration of advanced molecular tools, such as GeneXpert^®, represents significant progress, enabling rapid and accurate diagnosis of TB and facilitating early initiation of treatment.