In a packed ballroom on the first day of the 2020 Winter Clinical Dermatology Conference, Theodore Rosen, MD, reminded attendees to be mindful of infectious diseases in their everyday practice. As Dr Rosen noted, a number of infections, from sexually transmitted diseases (STDs) to insect-borne diseases, are on the rise on local, national, and global levels.
The session first detailed the resurgence of STDs. For the fifth-straight year, the annual number of STDs has increased in the United States, including a 19% increase in chlamydia, 63% increase in gonorrhea, and 71% increase in syphilis between 2014 and 2018. This trend is not limited to the US; European countries, such as Iceland, Ireland, the United Kingdom, and Germany, have seen significant increases in syphilis from 2007 to 2017 (876%, 224%, 153%, and 144% increase, respectively).
Clinicians may believe that these stark numbers are due to the ease of online “hook-up” culture (as Dr Rosen noted, “we can go online and get a sex partner faster than getting a pizza delivered”). However, data from two 2019 studies published in JAMA and Sexually Transmitted Diseases found that persons who participate in online dating tend to be better informed by crowd-sourcing information on STDs and were tested more frequently for STDs.
In addition to bacterial STDs, viral STDs are still relevant to the dermatologist. For external genital warts, there is no “best” treatment. “Three papers, looking at meta-analysis of all the common treatments for external genital warts, intended to show the best treatment. They came to different conclusions using the same data,” said Dr Rosen. Taking consideration of these three papers along with guidelines from the European Union, he suggested using a combination therapy, with a “destructive therapy” (eg, cryosurgery, carbon dioxide laser ablation) followed by a secondary therapy a week or two later. The human papillomavirus vaccine is a safe, preventative measure.
Dr Rosen briefly discussed HIV as a serious consideration for dermatologists. There are two new HIV vaccines: emtricitabine and tenofovir alafenamide (Descovy), and emtricitabine and tenofovir disoproxil fumarate (Truvada). He highlighted that a 2019 study in The Lancet conclusively supported the theory of “undetectable = untransmittable” by demonstrating zero HIV transmissions over a 2-year period when an HIV+ partner reliably took antiretroviral therapy.
A recent hot topic in the news, the measles outbreak has spread worldwide. World Health Organization statistics has found a 300% increase in the first half of 2019 compared with the same period in 2018. This outbreak has coincided with the anti-vaccination movement, which comes from religious and personal exemption requests. Dr Rosen noted that vaccination laws, which vary by state, often allow religious or personal exemptions; Maine, New York, West Virginia, Mississippi, and California currently allow medical exemptions only.
Mosquito-borne infectious diseases are also increasingly relevant to the dermatologist. Dengue, zika, and chikungunya are all well-known infections, but two new viruses are increasingly common. Mayaro virus, which originates in the Caribbean, Central America, and South America, can cause a nonspecific rash along with high fever, pain behind the eyes, arthralgia, myalgia, and more. Parechovirus, which has been found in Japan and Australia, causes a nonspecific or “mittens and booties” rash commonly seen in children less than 5 years of age.
Dermatologists should note the discovery of a new tick, the Asian longhorned tick (Haemaphysalis longicornis). While it is a native of China, Japan, and Korea and mostly in animals, this tick has been found in various states across the United States and there are two reports that found this tick in humans in the US. The Asian longhorned tick can be deadly – it can cause severe fever and thrombocytopenia syndrome. Dr Rosen advised “You got a tick? You get a doxycycline, and that’s the end of the story.”
Reference
Rosen T. Infectious disease update. Presented at: 2020 Winter Clinical Dermatology Conference; Kohala Coast, HI; January 18, 2020.