All four dengue virus serotypes co-circulate in concurrent dengue infections in a single dengue session in Chittagong, Bangladesh

Abstract

Purposes: Dengue fever, a mosquito-borne viral disease, is a global public health burden affecting millions of people each year and over 40% of world populations are at risk of dengue. Therefore, prompt and accurate dengue diagnosis is inevitable for disease surveillance and for aiding disease management. In this study we report dengue virus (DENV) seroprevalence in Chittagong, Bangladesh along with clinical manifestation of dengue infections. Methods: All samples included in this study were selected based on dengue NS1-based diagnosis, clinical sign and symptoms were judged by expert clinical physicians and infecting DENV serotyping was done by RT-PCR. The blood cells (Platelet, Haematocrit, WBC etc) were analyzed using Haematology cell counter. Results: First, among the 112 DENV infected serum samples tested by RT-PCR, 42 were DENV positive where 76% samples had single DENV serotype infection and 24% were concurrently infected with two or more DENV serotypes, indicating that all four DENVs were present in a single dengue session in Chittagong, Bangladesh. Then, DENV4 was the most prevailed serotype, followed by DENV2, DENV1 and DENV3 in single DENV serotype infections. However, in almost 90% cases of concurrent multiple DENV infections DENV1 serotype was present. A detail analysis of clinical data clearly indicated that DENV1 and DENV2 resulted very similar patterns of clinical symptoms which were quite different from those caused by DENV3 and DENV4. For example, ache and pain were absent in DENV3 infection and diarrhea was absent in DENV4 infections. Furthermore, DENV3, both in single and concurrent multiple DENV infections, might increase dengue disease severity as observed highly reduced platelet counts along with increased WBC in patients infected with DENV3 serotype. Conclusion: All four DENV serotypes, both as single and concurrent multiple DENV infections, were present in single dengue session in Bangladesh. Despite having very similar sequences and structures all four DENVs might produce different disease spectra, ranging from classical dengue fever to dengue hemorrhagic fever. Concurrent multiple DENV infections could contribute increased dengue disease severity in dengue outbreaks in Bangladesh. Bioresearch Commu. 8(1): 1042-1048, 2022 (January)

Prevalence of dengue virus, their infection, diagnosis, and challenges

“…This is perhaps originated from the inherent sequences of very similar but distinctive four DENV serotypes [15]. The typical clinical signs and symptoms of dengue disease include undifferentiated high fever, vomiting, musculoskeletal pain, myalgia, re-o-pain, rash, nausea, and headache which were observed in almost all cases of DENV infections [16] [Table 1]. A detail analysis indicated that DENV1 and DENV2 result very similar patterns of clinical symptoms which were quite different from those caused by DENV3 and DENV4, for example, ache-pain and diarrhea were absent in DENV3 and DENV4 infections, respectively [16].…”

“…The typical clinical signs and symptoms of dengue disease include undifferentiated high fever, vomiting, musculoskeletal pain, myalgia, re-o-pain, rash, nausea, and headache which were observed in almost all cases of DENV infections [16] [Table 1]. A detail analysis indicated that DENV1 and DENV2 result very similar patterns of clinical symptoms which were quite different from those caused by DENV3 and DENV4, for example, ache-pain and diarrhea were absent in DENV3 and DENV4 infections, respectively [16]. However, the number of samples analyzed in each category was very limited, therefore, vast number samples from different geolocations are worth considering for developing rationale for infecting DENV serotypes with clinical signs and symptoms of dengue infection.…”

“…On the other hand, the DENV4 has been the most dominant serotype since 1968 in Tamil Nadu with a shift in Clade C to D due to genetic distinction [18]. Interestingly, in the past, DENV3 was the most prevailed serotype in Bangladesh [19], Cameroon [20], and India [21], however, the 2016-2019 dengue outbreaks in Bangladesh had DENV4 as the foremost prevailed serotype, followed by DENV2, DENV1, and DENV3 serotypes [16]. Although any explanation for such DENV serotype replacement is yet to be available, such DENV serotype variation in recurrent dengue outbreaks might have impact on dengue incidence and dengue disease severity [22].…”

“…Moreover, not only the sero-conversion but also concurrent multiple DENV infections have been reported in many dengue endemic countries worldwide [23][24][25][26][27]. For example, 2018-2019 dengue outbreak in Chittagong, Bangladesh, had 24% concurrently multiple DENV infections (concurrently infected with more than 1 DENV serotype) [16]. Altogether, these observations clearly suggested that DENV serotyping based on clinical signs and symptoms and establishing association of infecting DENV serotypes and dengue severity are seemed more difficult that previously though [16].…”

Concurrent dengue infections: Epidemiology & clinical implications

“…There have been various reports from tropical and subtropical countries across the world of patients testing positive for heterosubtypic dengue infections 18 19 20 21 22 23 24 25 26 27 28 .…”