Serratia marcescens is an opportunistic gram-negative pathogen that causes pneumonia, bloodstream infections, and urinary tract infections, particularly in individuals who are immunocompromised. Although commonly associated with pulmonary infections, its involvement in pneumothorax-related infections is exceedingly rare. Secondary spontaneous pneumothorax (SSP) is a life-threatening condition that can complicate underlying lung diseases, such as chronic obstructive pulmonary disease (COPD). This case report describes a rare presentation of S. marcescens infection in a patient with SSP complicated by a bronchopleural fistula. A 64-year-old male with a history of COPD, chronic smoking, and alcohol use presented with progressive dyspnea, cough, and left-sided chest pain. Clinical evaluation revealed tachypnea, tracheal deviation, and reduced breath sounds in the left lung. Laboratory investigations revealed leukocytosis with marked neutrophilia and an elevated erythrocyte sedimentation rate. Chest imaging confirmed pneumothorax, necessitating intercostal drain (ICD) placement. Pleural fluid cultures identified multidrug-resistant S. marcescens, prompting antibiotic escalation to intravenous meropenem and oral faropenem. Despite prolonged antimicrobial therapy and ICD placement, persistent pneumothorax with a bronchopleural fistula was noted. Bronchoscopy with Fogarty balloon placement and cyanoacrylate closure was performed. However, owing to financial constraints, the patient declined follow-up cultures and high-resolution computed tomography imaging, and was discharged with an ICD in situ. This case underscores the need for heightened clinical awareness of S. marcescens in pneumothorax-associated infections. Early microbiological identification and targeted therapy are crucial for the management of rare yet challenging presentations, particularly in resource-limited settings.

Rhipicephalus microplus, known as the hard tick, is a vector for the parasites Babesia spp. and Anaplasma marginale, both of which can cause significant financial losses to the livestock industry. There is currently no effective vaccine for R. microplus tick infestations, despite the identification of numerous prospective tick vaccine candidates. As a result, the current research set out to develop an immunoinformatics-based strategy using existing methods for designing a multi-epitope based vaccination that is not only effective but also safe and capable of eliciting cellular and humoral immune responses. First, R. microplus proteins Bm86, Subolesin, and Bm95 were used to anticipate and link B and T-cell epitopes (HTL and CTL) to one another. Antigenicity testing, allergenicity assessment, and toxicity screening were just a few of the many immunoinformatics techniques used to identify potent epitopes. Multi-epitope vaccine design was chosen based on the antigenic score 0.935 that is promising vaccine candidate. Molecular docking was used to determine the nature of the interaction between TLR2 and the vaccine construct. Finally, molecular dynamic simulation was used to assess the stability and compactness of the resulting vaccination based on docking scores. The developed vaccine was shown to be stable, have immunogenic qualities, be soluble, and to have high expression by in silico cloning. These findings suggest that experimental investigation of the multi-epitope based vaccine designed in the current study will produce achievable vaccine candidates against R. microplus ticks, enabling more effective control of infestations.

Anaplasma marginale is the most prevalent tick-borne haemoparasite of cattle and causes huge economic losses to the dairy industry worldwide. This study aimed to determine the occurrence of A. marginale infection in blood and tick samples collected from livestock animals in the districts located in Khyber Pakhtunkhwa (KPK), Pakistan. A total of 184 blood and 370 tick samples were included in this study. It has never been reported that sheep, goats, and cattle in Tank, Ghulam Khan, Birmil and Miran Shah areas were infected with A. marginale. All samples of blood and ticks were collected through random sampling from March 2021 to January 2022 from cattle, sheep and goats and screened through PCR for anaplasmosis by using primer pairs of Anaplasma spp. Three hundred and seventy ticks were collected from infested hosts (120/184, 64.21%). Among the four morphologically identified tick species, the highest occurrence was recorded for Rhipicephalus sanguineus (n=138, 37.29%), followed by Rhipicephalus microplus (n=131, 35.4%), Rhipicephalus annulatus (n=40, 10.81%), Hyalomma anatolicum (n=31, 8.37%), and Hyalomma marginatum (n=30, 8.1%). The occurrence of female tick was highest (n=160, 43.24%), followed by nymphs (n=140, 37.38%) and males ticks (n=70, 18.9%). Among these ticks, A. marginale was detected in female ticks of R. microplus, and R. sanguineus. Molecular identification of A. marginale was confirmed in 120 out of 184 blood samples and 6 out of 74 tick samples. Overall, occurrence of A. marginale in blood and tick samples was found to be 65.21% and 8.1% respectively. Species-wise occurrence in blood samples of goats were 71.11% followed by sheep 68.31% and cattle 50%. Specie-wise occurrence of A. marginale in tick samples of cattle were 12.5% followed by goats 6.89%. The obtained sequence showed similarity with A. marginale reported from Kenya and USA. We report the first PCR based detection of A. marginale infection in blood samples and in R. sanguineus ticks of goats simultaneously.