The 1993 dengue 2 epidemic in Charters Towers, North Queensland: clinical features and public health impact

Abstract

In 1993 an epidemic caused by dengue virus type 2 occurred in several North Queensland population centres. Charters Towers, estimated population 10,000, had 155 officially notified cases. An analysis of symptoms was undertaken using a random sample of 1000 residents to determine specificity of symptoms, the subclinical infection rate, and to establish the true extent of the epidemic. Retrospective diagnoses of dengue fever were based on the presence of both serum dengue 2 neutralizing antibody and presence of symptoms. An estimated 20% of the population had dengue fever. The rate of subclinical infections in this epidemic was 14.6%. There were no symptoms that were specific for dengue fever. Bleeding occurred more frequently in people who recalled a previous dengue infection during a dengue 1 epidemic 12 years earlier (55.6% vs. 16.8%, P = 0.003). Surveillance for future epidemics should be based on serological and virological confirmation of dengue virus infection amongst symptomatic patient.

Incidence and seroprevalence of dengue virus infections in Australian travellers to Asia

“…In addition, whilst data on previous travel or residence in Northern Queensland was not specifically collected, seroprevalence could be attributed to previous exposure to dengue or other local flaviviruses, such as Kunjin or Murray Valley encephalitis virus. There is conflicting data on age and gender association with dengue seroprevalence in non-endemic countries [30,33] and whilst over two-thirds of the travellers with evidence of past dengue infection were older than the median age of the current cohort, the association between age and seroprevalence was not found to be significant. DHF has been described infrequently in travellers and there are no studies reporting on the incidence of DHF in travellers [9][10][11].…”

“…The 20 travellers with pre-existing antibodies for dengue infection in the current study did not report a past history of dengue infection. The rates of clinical-to-subclinical infection identified in studies of local endemic populations have ranged from 1:0.2 to 1:7 [30][31][32], and the determinants of clinical versus subclinical infection are not clearly defined. Infecting DENV strains, cross-reactive immunity from infection with different DENV serotypes and pre-existing host immunity may play a role.…”

Clinical and laboratory features that discriminate dengue from other febrile illnesses: a diagnostic accuracy study in Rio de Janeiro, Brazil

“…Nevertheless, taste alteration was reported as a dengue predictor by the few researchers who investigated this symptom [15,39], and conjunctival redness was reported by Low et al . [15] as one of the most accurate signs (p < 0.0005; OR = 4.49) for dengue diagnosis among adult outpatients with a fever lasting less than 72 hours.…”

Contribution of Dengue Fever to the Burden of Acute Febrile Illnesses in Papua New Guinea: An Age-Specific Prospective Study

“…It is recognized that asymptomatic infections are thought to be uncommon, at least in adult Caucasian and Asian populations. 5,6 However, several studies have shown that the rate of asymptomatic infections can be much higher in the pediatric population. 7 Since the 1960s, millions of people have been affected by DF, and many have died as a consequence of DHF.…”