Evidence of chikungunya virus infection among febrile patients seeking healthcare in selected districts of Tanzania

Figures & data

Figure 1. Map of Tanzania showing study locations which included four districts (highlighted in green) located within four regions (highlighted in yellow).

Table 1. Clinical features of febrile patients in Karagwe, Sengerema, Kilombero and Kyela districts of Tanzania.

	Number of subjects (%)
Clinical symptoms/signs	Yes	No	Unknown
Fever	728 (100.00)	0 (0.0)	0 (0.0)
Headache	510 (70.0)	200 (27.5)	18 (2.5)
Nausea	402 (55.3)	290 (39.8)	36 (5)
Vomiting	448 (61.5)	280 (38.5)	0 (0.0)
Joint ache	497 (68.3)	231 (31.8)	0 (0.0)
Stiff neck	246 (33.8)	426 (58.5)	56 (7.8)
Seizures	264 (36.3)	457 (62.8)	7 (1.0)
Leg weaknesses	433 (59.5)	246 (33.8)	49 (6.8)
Skin rash	189 (26.0)	539 (74.0)	0 (0.0)
Abdominal pains	304 (41.8)	424 (58.3)	0 (0.0)
Pallor	395 (54.3)	333 (45.8)	0 (0.0)
Jaundice	411 (56.5)	317 (43.5)	0 (0.0)
Laboured breathing	422 (58.0)	306 (42.0)	0 (0.0)

Table 2. Seroprevalence of anti-CHIKV-IgG among febrile patients in Karagwe, Kilombero, Kyela and Sengerema districts.

Districts	No. of patients	No. of IgG positive	Seropositivity (%)	Seronegativity (%)
Karagwe	182	49	49 (26.9)	133 (73.1)
Kilombero	182	19	19 (10.4)	163 (89.6)
Kyela	182	14	14 (7.7)	168 (92.3)
Sengerema	182	23	23 (12.6)	159 (87.4)
Total	728	105	105 (14.4)	623 (85.6)

Table 3. Comparison between clinical features and demographic characteristics of study participants with acute chikungunya infection in Karagwe, Kilombero, Kyela and Sengerema districts.

Characteristics	Acute CHIKV infection Overall seropositivity: 11/728 (1.5%)		No acute CHIKV infection Overall seronegativity: 717/728 (98.5%)
Total	n = 11	%	n/N	%
Demographics
Gender
Male	2	(18.2)	264/266	99.2
Female	9	(81.8)	453/462	98.1
Districts
Karagwe	5	(45.5)	177/182	97.3
Kilombero	2	(18.2)	180/182	98.9
Kyela	3	(27.3)	179/182	98.4
Sengerema	1	(9.1)	181/182	99.5
Clinical signs and symptoms
Headache	3	(27.3)	507/510	99.4
Nausea	0	(0.0)	402/402	100
Vomiting	1	(9.1)	447/448	99.8
Joint ache	7	(63.6)	490/497	98.6
Stiff neck	0	(0.0)	246/246	100
Seizures	0	(0.0)	264/264	100
Leg weaknesses	2	(18.2)	431/433	99.5
Skin rash	6	(54.5)	183/189	96.8
Abdominal pains	1	(9.1)	303/304	99.7
Pallor	0	(0.0)	395/395	100
Jaundice	0	(0.0)	411/411	100
Laboured breathing	3	(27.3)	419/422	99.3

Table 4. The proportion of seroprevalence of chikungunya virus infection by age group.

Age group (years)	No. of participants	No. (%) of IgG positive	No. (%) of IgM positive	P value
1–9	87	3 (3.5%)	1 (1.2%)	0.3
10–19	169	11 (6.5%)	4 (2.4%)	0.06
20–29	184	66 (35.9%)	5 (2.7%)	<0.001
30–39	116	19 (16.4%)	1 (0.9%)	<0.001
40–49	66	2 (3.0%)	0 (0.0%)	-
≥50	106	4 (3.8%)	0 (0.0%)	-