Update on the Diagnosis of Sexually Transmitted Infections

International travels and transmission of multidrug resistant Neisseria gonorrhoeae in Europe: A systematic review

BACKGROUND

The increase of gonococcal infection cases in Europe and rises in Neisseria gonorrhoeae antibiotic resistance (AMR) have become an urgent concern globally. In the last few years international tourism has increased, which might contribute to the spread of different strains of multiresistant gonococcal infections. This study aimed at assessing the effect of international travel on the transmission of multidrug resistant N. gonorrhoeae in the European Union and associated European countries.

METHOD

We conducted a systematic review and searched PubMed, Scopus, Embase and CENTRAL between January 1, 2010 and June 30, 2021 for gonococcal infection, antibiotic resistance and international travel. Articles were screened in title, abstract and keywords. The quality of the articles was assessed using a pre-designed tool. Individual, travel related and susceptibility to antimicrobials data were collected.

RESULTS

A total of 18 studies met our criteria, of which 88.9% concluded that international travel directly influences the transmission of multidrug resistant N. gonorrhoeae from the country of travel to the country of return. Travelers mainly visited South East Asian countries (66.7%) and returned to the UK (38.9%). Half of the included studies reported ciprofloxacin resistant strains and the most frequently prescribed drug used for treatment was ceftriaxone.

CONCLUSIONS

International travels might be an important factor in the spread of multi-resistant sexually transmitted infections (STIs). There is a need to strengthen AMR surveillance in international travelers for prompt investigation and notification of drug resistance in STIs.

Stochastic Petri net model describing the relationship between reported maternal and congenital syphilis cases in Brazil

INTRODUCTION

Syphilis is a sexually transmitted disease (STD) caused by Treponema pallidum subspecies pallidum. In 2016, it was declared an epidemic in Brazil due to its high morbidity and mortality rates, mainly in cases of maternal syphilis (MS) and congenital syphilis (CS) with unfavorable outcomes. This paper aimed to mathematically describe the relationship between MS and CS cases reported in Brazil over the interval from 2010 to 2020, considering the likelihood of diagnosis and effective and timely maternal treatment during prenatal care, thus supporting the decision-making and coordination of syphilis response efforts.

METHODS

The model used in this paper was based on stochastic Petri net (SPN) theory. Three different regressions, including linear, polynomial, and logistic regression, were used to obtain the weights of an SPN model. To validate the model, we ran 100 independent simulations for each probability of an untreated MS case leading to CS case (PUMLC) and performed a statistical t-test to reinforce the results reported herein.

RESULTS

According to our analysis, the model for predicting congenital syphilis cases consistently achieved an average accuracy of 93% or more for all tested probabilities of an untreated MS case leading to CS case.

CONCLUSIONS

The SPN approach proved to be suitable for explaining the Notifiable Diseases Information System (SINAN) dataset using the range of 75-95% for the probability of an untreated MS case leading to a CS case (PUMLC). In addition, the model's predictive power can help plan actions to fight against the disease.

Bridging the gap between development of point-of-care nucleic acid testing and patient care for sexually transmitted infections

The incidence rates of sexually transmitted infections (STIs), including the four major curable STIs - chlamydia, gonorrhea, trichomoniasis and, syphilis - continue to increase globally, causing medical cost burden and morbidity especially in low and middle-income countries (LMIC). There have seen significant advances in diagnostic testing, but commercial antigen-based point-of-care tests (POCTs) are often insufficiently sensitive and specific, while near-point-of-care (POC) instruments that can perform sensitive and specific nucleic acid amplification tests (NAATs) are technically complex and expensive, especially for LMIC. Thus, there remains a critical need for NAAT-based STI POCTs that can improve diagnosis and curb the ongoing epidemic. Unfortunately, the development of such POCTs has been challenging due to the gap between researchers developing new technologies and healthcare providers using these technologies. This review aims to bridge this gap. We first present a short introduction of the four major STIs, followed by a discussion on the current landscape of commercial near-POC instruments for the detection of these STIs. We present relevant research toward addressing the gaps in developing NAAT-based STI POCT technologies and supplement this discussion with technologies for HIV and other infectious diseases, which may be adapted for STIs. Additionally, as case studies, we highlight the developmental trajectory of two different POCT technologies, including one approved by the United States Food and Drug Administration (FDA). Finally, we offer our perspectives on future development of NAAT-based STI POCT technologies.

Two for One: Concurrent Acquisition of Molluscum Contagiosum Infection and Scabies Infestation After a Single Sexual Encounter

Molluscum contagiosum and scabies are contagious conditions that can be acquired by incidental casual contact of a disease-free individual with an infected person. However, both the viral infection and the mite infestation can be transmitted sexually from the infected person to the unsuspecting recipient partner. A 20-year-old man without any infectious diseases acquired not only molluscum contagiosum but also scabies after a single sexual encounter with a female partner; hence, he developed two sexually transmitted diseases after one sexual episode: two for one. He presented for medical attention to evaluate the new white umbilicated papules on his penile shaft and red nodules on the corona and glans of his penis. A complete skin examination also revealed additional papules on his abdomen and suprapubic region and a burrow on his left index finger adjacent to the finger web. Diagnosis of the molluscum contagiosum infection was confirmed by observing molluscum bodies on the molluscum preparation taken from an abdominal papule and the scabies infestation was confirmed by noting not only mite eggs but also mite scybala (feces) on the scabies (mineral oil) preparation from the burrow. The molluscum contagiosum infection was treated with curettage of the lesions. The scabies infestation was treated with two treatments (each one week apart) of permethrin five percent cream overnight topical application from his neck to his toes. All his lesions resolved and did not recur. In conclusion, the development of a new sexually transmitted disease in an individual should prompt the clinician to evaluate the patient for additional sexually transmitted diseases since the patient may have acquired more than one infection from their partner during the sexual encounter.