Clinical Features and Laboratory Findings of Travelers Returning to South Australia with Dengue Virus Infection
Abstract
:1. Introduction
2. Materials and Methods
2.1. Sample Collection
2.2. Serological Testing for DENV
2.3. RNA Extraction and pan-DENV RT-PCR
2.4. Serotype-Specific DENV RT-PCR and ZIKV RT-PCR
2.5. Data Analysis
3. Results
3.1. Dengue Positive Samples Represent a Minority of DENV Test Requests and Are Mostly NS1/IgM Positive
3.2. Demographics of the Patient Cohort with Clinical Dengue Serology Requests
3.3. Clinical Presentations and Laboratory Measurements in the Patient Cohort with Clinical DENV Serology Requests
3.4. Reliable Detection of DENV by RT-PCR Requires Multiple PCR Approaches and Detects DENV-1, -2 and -3 Serotypes
4. Discussion
5. Conclusions
Acknowledgments
Author Contributions
Conflicts of Interest
References
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RT-PCR | Sequence | Ref. | |
---|---|---|---|
Pan-DENV | Forward | AAGGACTAGAGGTTAKAGGAGACCC | |
Reverse | CGYTCTGTGCCTGGAWTGATG | [15] | |
Probe | FAM-TCTGGTCTTTCCAGCGTCAATATGCTGTT-BHQ | ||
DENV-1 | Forward | GACACCACACCCTTTGGACAA | [17] |
Reverse | CACCTGGCTGCTACCTCCAT | ||
DENV-2 | Forward | GACCACACGYAACGGAGAA | [17] |
Reverse | TCTGTTTTRAACAGRAGACTTTT | ||
DENV-3 | Forward | GGGAARACCGTCTATCAATA | [17] |
Reverse | CGCCATAACCAAYTTCATTGG | ||
DENV-4 | Forward | TGAAGAGATTCTCAACCGGAC | [17] |
Reverse | AATCCCTGCTGTTGGTGGG | ||
ZIKV | Forward | CCTTGGATTCTTGAACGAGGA | [18] |
Reverse | AGAGCTTCATTCTCCAGATCAA |
Diagnostic Parameter | # Number (%) Seropositive | RT-PCR | |||
---|---|---|---|---|---|
# of samples | Pan-DENV PCR positive | Positive by any PCR | |||
NS1 positive | 18 (37%) | 12 | 5 (42%) | 10 (83.3%) | |
IgM positive | 9 (18%) | 3 | 0 | 3 (100%) | |
IgM & NS1 positive | 16 (33%) | 12 | 7 (58%) | 10 (83.3%) | |
IgM & IgG positive | 3 (6%) | 2 | 0 | 2 (100%) | |
IgG & NS1 positive | 1 (2%) | 1 | 1 (100%) | 1 (100%) | |
IgM, IgG & NS1 positive | 2 (4%) | 2 | 1 (50%) | 2 (100%) | |
TOTAL Convalescence follow-up | 49 5 (10%) | 14/32 (43.8%) | 28/32 (87.5%) | ||
Initial result | Follow up result | Days post test | |||
NS1 positive | IgM positive | 6 | |||
IgM positive | IgM positive | 15 | |||
NS1 positive | IgM positive | 19 | |||
IgM positive | IgM positive | 20 | |||
NS1 positive | IgG & IgM | 22 |
DENV Seropositive | DENV Seronegative | p-Value | |
---|---|---|---|
Number of Patients | 49 | 51 | |
Age (Years), median (Range) | 40 (27.75–51.5) | 33.5 (22.75–55.5) | |
Gender | |||
Male | 24 (48.98%) | 37 (60.66%) | 0.2505 |
Female | 25 (51.02%) | 24 (39.34%) | |
Centre of care | |||
Hospital | 27 (55.10%) | 39 (64.93%) | 0.4340 |
Community | 22 (44.90%) | 22 (36.07%) |
Travel Destination | DENV Seropositive | DENV Seronegative |
---|---|---|
Number of patients | 49 | 51 |
Unrecorded travel history | 12 (24.5%) | 10 (19.6%) |
Nil recent travel history | 0 | 2 (3.9%) |
Southeast Asia | 36 (73.5%) | 31 (60.8%) |
Indonesia | 21 (42.9%) | 12 (23.5%) |
Thailand | 6 (12.2%) | 6 (11.8%) |
Vietnam | 1 (2.0%) | 2 (3.9%) |
Singapore/Malaysia | 4 (8.2%) | 2 (3.9%) |
Philippines | 1 (2.0%) | 1 (2.0%) |
Borneo | 1 (2.0%) | 0 |
Cambodia | 0 | 4 (7.8%) |
Myanmar | 1 (2.0%) | 1 (2.0%) |
Other (unspecified) | 1 (2.0%) | 3 (5.9%) |
Australia | 0 | 3 (5.9%) |
North Queensland | 0 | 3 (5.9%) |
Pacific Islands | 1 (2.0%) | 5 (9.8%) |
Tonga | 1 (2.0%) | 0 |
Fiji | 0 | 3 (5.9%) |
Vanuatu | 0 | 2 (3.9%) |
Indian subcontinent | 3 (6.1%) | 2 (3.9%) |
India | 2 (4.1%) | 1 (2.0%) |
Pakistan | 0 | 1 (2.0%) |
Bangladesh | 1 (2.0%) | 0 |
Africa | 0 | 2 (3.9%) |
Tanzania | 0 | 1 (2.0%) |
Guinea | 0 | 1 (2.0%) |
Hong Kong | 0 | 1 (2.0%) |
Papua New Guinea | 0 | 2 (3.9%) |
Recent travel declared (destination unspecified) | 0 | 4 (7.8%) |
Symptom | DENV Seropositive | DENV Seronegative | p-Value |
---|---|---|---|
Fever | 37 (95%) | 36 (71%) | 0.0054 |
Headache | 16 (41%) | 16 (31%) | 0.3801 |
Retro-orbital pain | 0 (0%) | 1 (2%) | 1 |
Nausea and/or vomiting | 10 (26%) | 16 (31%) | 0.6418 |
Swollen glands | 0 (0%) | 0 (0%) | 1 |
Myalgia and/or arthralgia | 22 (56%) | 19 (37%) | 0.0890 |
Rash | 14 (36%) | 4 (8%) | 0.0013 |
Grouping | Specific Diagnosis 35/51, 68.6% |
---|---|
Gastroenteritis | Total, n = 5 (13.5%) Shigella spp. Salmonella spp. (n = 2) Salmonella typhi (n = 2) |
Respiratory | Total, n = 10 (27%) Influenza A virus (n = 5) Pneumonia (n = 2) Viral pharyngitis Parainfluenza 1 with COPD Rhinovirus with adenovirus |
Parasitic | Total, n = 6 (21.6%) Malaria (n = 3) Cryptosporidium Hydatid disease Giardia |
Other | Total, n = 11 (29.7%) |
Infectious | Total, n = 7 Infected lymphocoele Spontaneous peritonitis Streptococcus pyogenes bacteremia Polymicrobial wound infection Measles virus E coli urosepsis Infective endocarditis Febrile or ‘viral’ illness (n = 3) |
Non-infectious | Total n = 4 Haemophagocytic lymphohistocytosis Phototoxic rash Gastric diffuse large B-cell lymphoma Benign headache |
No specific diagnosis | Total, n = 16 (31.4%) |
Laboratory Measure | Reference Range | DENV Seropositive Median (IQR) | DENV Seronegative Median (IQR) | p-Value |
---|---|---|---|---|
Haemoglobin | ||||
Female | (115–155 g/L) | 132.5 (128–143.25) | 140 (137–148) | 0.680 |
Male | (135–175 g/L) | 149 (134–155.5) | 140.5 (135.25–153) | 0.316 |
Platelets | (150–450 ×109/L) | 140 (106.5–183.8) | 231 (165.5–277.5) | <0.0005 |
Haematocrit | (0.35–0.45) | 0.42 (0.39–0.43) | 0.41 (0.393–0.43) | 0.520 |
White cell count | (4.00–11.0 ×109/L) | 2.8 (2.1–4.8) | 7.41 (5.295–9.8) | <0.0005 |
Lymphocytes | (1.50–3.50 ×109/L) | 0.79 (0.54–1.32) | 1.28 (0.98–2.045) | 0.0218 |
Neutrophils | (1.80–7.50 ×109/L) | 1.67 (1.15–2.71) | 4.91 (3.595–8.36) | <0.0005 |
CRP | (<8.0 mg/L) | 7.25 (4.5–16) | 51.5 (15.75-91.5) | <0.0005 |
Pan-DENV | No Serotype Determined | Mixed Serotype Result | DENV-1 | DENV-2 | DENV-3 | DENV-4 | |
---|---|---|---|---|---|---|---|
Pan-DENV positive | 14 | 4 | 5 | 1 | 4 | 0 | 0 |
Pan-DENV negative | 18 | 4 | 2 | 4 | 7 | 1 | 0 |
DENV-1 | - | 5 | 5 | 0 | 0 | ||
DENV-2 | - | 5 | 11 | 2 | 0 | ||
DENV-3 | - | 0 | 2 | 1 | 0 | ||
DENV-4 | - | 0 | 0 | 0 | 0 |
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Share and Cite
Quinn, E.J.; Cheong, A.H.-C.; Calvert, J.K.; Higgins, G.; Hahesy, T.; Gordon, D.L.; Carr, J.M. Clinical Features and Laboratory Findings of Travelers Returning to South Australia with Dengue Virus Infection. Trop. Med. Infect. Dis. 2018, 3, 6. https://doi.org/10.3390/tropicalmed3010006
Quinn EJ, Cheong AH-C, Calvert JK, Higgins G, Hahesy T, Gordon DL, Carr JM. Clinical Features and Laboratory Findings of Travelers Returning to South Australia with Dengue Virus Infection. Tropical Medicine and Infectious Disease. 2018; 3(1):6. https://doi.org/10.3390/tropicalmed3010006
Chicago/Turabian StyleQuinn, Emma J., Allena H.-C. Cheong, Julie K. Calvert, Geoffrey Higgins, Trish Hahesy, David L. Gordon, and Jillian M. Carr. 2018. "Clinical Features and Laboratory Findings of Travelers Returning to South Australia with Dengue Virus Infection" Tropical Medicine and Infectious Disease 3, no. 1: 6. https://doi.org/10.3390/tropicalmed3010006