Skin Signs That Could Help You Diagnose Arboviruses Faster

Fever, headache, muscle pain, nausea, and diarrhea are hallmark symptoms of dengue and other arbovirus infections. However, dermatological manifestations are also common in diseases such as Zika, chikungunya, and Oropouche fever.

Dermatologists should be equipped to recognize these infections, especially in patients from endemic tropical regions, according to a presentation at the 15th World Congress of Pediatric Dermatology (WCPD) held in Buenos Aires, Argentina, from April 7 to 11, 2025.

“Generally, when people have skin lesions, they consult a dermatologist. Therefore, it is necessary for dermatologists to have knowledge of the four main arboviruses [in the region] and be prepared to make a differential diagnosis,” Omar Lupi, MD, PhD, associate professor of dermatology at the Federal University of the State of Rio de Janeiro, professor of immunology at the Federal University of Rio de Janeiro, both in Rio de Janeiro, Brazil, and current president of the Ibero-Latin American College of Dermatology, told Medscape’s Spanish edition.

Lupi emphasized that dengue is the “most difficult arbovirus to control because it is distributed worldwide.” He noted that the symptoms of classic dengue include exanthematous lesions that may appear as “white islands in a red sea” (normal skin interspersed with erythema). In severe or hemorrhagic dengue, the skin may appear pale, cold, and moist with purpuric or petechial lesions.

Chikungunya’s Dermatological Impact 

Regarding chikungunya fever, Lupi highlighted that dermatological manifestations occur in 40%-50% of cases, with morbilliform eruptions being the most common pattern. These lesions typically appear 3-5 days after fever onset and resolve within 3-4 days. The rash is asymptomatic in 80% of patients, whereas the remaining 20% experience mild pruritus. “Chikungunya may not only present with exanthema but also with hypermelanosis, such as melasma, freckles, or acute intertrigo [inflammatory rashes in skin folds] similar to lesions caused by genital herpes.”

Rare and severe cases may also occur. In 2020, Lupi and his colleagues published a case of congenital chikungunya transmission that resulted in extensive skin lesions in a newborn, resembling staphylococcal scalded skin syndrome, toxic epidermal necrolysis, or epidermolysis bullosa.

A poster presented at the congress described the case of a 6-year-old Paraguayan boy who had chikungunya fever and, a month and a half later, developed chronic lichenoid pityriasis, an inflammatory dermatosis characterized by persistent erythematous scaly papules distributed on the trunk and limbs.

Zika’s Rash

In Zika virus infection, maculopapular rash (usually pruritic) is a common sign, although it manifests earlier than in dengue. Its prevalence varies; it was observed in 100% of individuals during a 2007 outbreak in Micronesia, but only 1 in 3 patients affected in 2009 in Senegal and the United States. To date, only two cases of hemorrhagic manifestations have been reported.

‘A Clinical Frankenstein’

Lupi addressed what he considers a growing threat in the region: Oropouche fever, a virus first identified in 1955 in Trinidad and Tobago. It has caused outbreaks in jungle regions along the Amazon River Basin and has presented cases in Brazilian cities such as São Paulo and Rio de Janeiro.

With more than 30,000 cases described since 1955 in Latin America, approximately 60% of patients present with skin lesions, mainly exanthema (20%-40%) and petechiae or other hemorrhagic manifestations (5%). Conjunctival injection has been reported in 20%-40% of cases. The rash may disappear and reappear 15-28 days after the acute febrile phase.

Most patients recover within 1-2 weeks, but in 2024, the first deaths were reported: Two young women from a nonendemic area of Brazil (Bahia) who experienced rapid progression (4-5 days) from initial symptoms to death. Among other symptoms indistinguishable from severe dengue, “both presented blurred vision and skin rash, and one had gingival hemorrhagic lesions and disseminated petechiae,” Lupi stated.

Lupi added that Oropouche fever is a ‘clinical Frankenstein’ as it combines symptoms seen in multiple arboviral infections. Similar to dengue, it can present with conjunctival injections, headache, fever, hemorrhages, weakness, and a nonpruritic rash. It shares neurological complications with Zika, including an increased risk for Guillain-Barré syndrome and microcephaly. General malaise, arthralgia, and myalgia, commonly associated with chikungunya, are also observed in Oropouche fever. Additionally, it can lead to meningitis, a complication more typically associated with the West Nile virus.

Differentiating Arboviruses 

“From a practical dermatological perspective, is there any special characteristic that allows differentiation between the various arboviruses?” Medscape’s Spanish edition asked Lupi.

“Dengue has more hemorrhagic manifestations; Zika has more itching; chikungunya involves significant joint pain; and in Oropouche, it is common for skin lesions to relapse after an initial improvement,” he replied.

Prevention Challenges 

Preventive measures are the same as for other mosquito-borne infections: Reducing vector breeding areas, educating travelers, wearing long-sleeved white clothing, using nets or mesh screens, and applying repellents.

“But with Oropouche, we have a major issue: Studies show that N, N-diethyl-meta-toluamide, the main component of repellent products, is not effective in reducing bites from the vector midge (Culicoides paraensis). Other commercial repellents also failed to inhibit the midge’s host-seeking behavior,” Lupi concluded.

Lupi had declared no relevant financial conflicts of interest.

This story was translated from Medscape’s Spanish edition using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.