RATZOOMAN PROJECT PROGRESS REPORT (JAN. – SEPT. 2004) …projects.nri.org/ratzooman/docs/Tanzania...

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RATZOOMAN PROJECT

PROGRESS REPORT (JAN. – SEPT. 2004)

PEST MANAGEMENT CENTRE

SOKOINE UNIVERSITY OF AGRICULTURE [USOKA]

MOROGORO

TANZANIA

INTRODUCTION

Between January and September 2004, studies continued in urban and peri-urban Morogoro (major area of study) and in Lushoto(minor area). The packages covered include: -

Investigation of human and animal sera for zoonotics (WP 1).

Identification of rodent species (WP 2), to be reported also byRUCA /DPIL.

Isolation and characterization of zoonotics from rodents andshrews (WP 3).

Socio-economic impact of rodent transmitted diseases (WP 6).

Socio-anthropogenic change upon rodent ecology (WP 7 -

WP6 and WP7 to reported by NRI.)

RETROSPECTIVE AND PROSPECTIVE INVESTIGATION OF HUMAN SERA (WP 1).

Human sera were obtained in the first year (2003) of the projectthrough on going epidemiological studies including: HIV, MALARIA, TYPHOID, and from diagnostic labs.

Major sources were obtained from referral hospitals serum banksnamely, Kilimanjaro Christian Medical College-KCMC (Moshi) and the Muhimbili University College of Health Sciences-MUCHS (Dar-Es–Salaam ).

Other sources of the sera included: Agha Khan Hospital (AGKH), Upendo Laboratory (UML) and Mikumi Health Centre (MHC) in Morogoro (Table 1).

Table 1: -Sources of human sera

Period (2003)

Region Source Samples

May - June Morogoro AGKH 336

May Morogoro UML 325

May - July Morogoro MHC 290

May - July Kilimanjaro KCMC 352

July-Sept. Dar - Es -Salaam

MUCHS 399

TOTAL 1702

Table 2a: MAT of human sera (n = 150) from Aga Khan Hospital,Morogoro

Serovars testedTitresIctero. Hardjo Pomona Canicola Ballum

1:20 1 1 1 11:40 1 11:80 21:160 1 11:3201:640 11:1280 1 1

Total (%) 5 (3.33) 4 (2.67) 2 (1.33) 0 2 (1.33)

SEROLOGICAL (MAT) ANALYSIS FOR ZOONOTICS OF HUMAN SERA SAMPLES

Serum samples (n = 400) collected from the main area of study (Morogoro) were randomly selected and analysed by MAT.

Five serovars of leptospira (ss) were used as antigens, including: Pomona, Canicola, Ballum, Hardjo and Icterohaemorrhagiae (Table 2 a,b and c).

Serovar Icterohaemorrhagiae was the local isolate RMI (previously typed by KIT).

Selected samples were first screened at 1:20 – 1:160 then positives were titrated to their respective endpoints.

Titres ranged from 1:20 up to 1:2560, majority of samplesbeing between 1:40 and 1:160.

Table 2b: MAT of human sera (n = 150) from Upendo Medical Laboratory, Morogoro

Serovars testedTitres Ictero. Hardjo Pomona Canicola Ballum

1:20 71:40 4 21:80 21:160 21:320 11:640Total (%) 15 (10) 3 (2) 0 0 0

Table 2c: MAT of human sera (n = 100) MAT from Mikumi Health Center, Morogoro

Serovars testedTitres Ictero.(RM1) Hardjo Pomona Canicola Ballum

1:20 4 2 2 11:40 5 11:80 9 1 41:160 3 11:320 21:640 11:2560 1Total (%) 23 (23) 5 (5) 2 (2) 7 (7) 0

IDENTIFICATION OF CAPTURED RODENT SPECIES (WP 2).

Trapping was carried out monthly in Morogoro between Januaryand September in human residence and peri-domestics, including: home gardens, cultivated fields and fallow swamps. Intensive trapping was in June, July and August 2004.

Total 2065 (1921 rodents,144 shrews), and 950 (833 rodents, 177shrews) were captured in 2003 and 2004, respectively (Tables 3,4).

Preliminary identification of the captures of 2004 to genusand/or species level are as shown in Table 4.

Further details shall be reported by RUCA/DPIL.

Table 3: Rodent and shrews captured in urban and peri-urbanMorogoro (February-December 2003)

Animals Period of collectionFeb Mar Apr May Jun Jul. Aug Sep Oct Nov Dec Tot.

M. natalensis 213 32 0 0 0 183 328 177 40 10 29 1012Crocidura spp. 59 17 4 0 4 13 16 22 0 4 5 144R.rattus 104 14 37 38 22 29 21 7 30 10 1 313R.norvegicus 10 4 5 0 2 6 2 4 0 0 0 33Mus spp. 154 111 20 15 17 24 21 4 2 0 0 368C. gambianus 1 20 23 9 18 21 5 9 14 1 0 121Tatera spp. 5 3 0 0 0 3 12 4 2 3 3 38Lemniscomys spp. 5 3 0 0 0 0 3 0 0 0 0 11Grammomys spp. 0 0 0 0 0 0 5 1 1 2 1 10Leggada spp. 0 0 0 0 0 3 1 1 1 1 2 9Dasymis spp. 0 0 0 0 0 0 2 2 0 0 0 4Praomys spp. 2 0 0 0 0 0 0 0 0 0 0 2Steatomys spp. 1 0 0 0 0 0 0 0 0 0 0 1Arvicanthis spp. 0 0 0 0 0 0 1 0 0 0 0 1Total 554 204 89 62 63 290 422 227 88 28 38 2065

Table 4: Rodents and shrews captured in urban and peri-urban Morogoro (January – September 2004)

Period of collectionAnimalsJan Feb Mar May June July Aug Sept Total

M.natalensis 39 0 45 48 30 214 187 105 668Crosidura spp. 4 0 15 24 13 18 37 6 117R. rattus 23 0 0 8 47 2 0 2 82R. norvegicus 0 0 0 0 2 0 0 0 2Mus spp. 2 0 0 0 36 0 0 0 38C.gambianus 2 4 0 0 9 2 0 0 17Tatera spp. 5 0 1 0 0 1 1 0 8Lemniscomys spp. 2 0 0 0 0 0 0 0 2Grammomys spp. 0 0 0 0 0 1 2 0 11Leggada spp. 0 0 0 1 0 0 1 18 3Dasymis spp. 0 0 0 0 0 0 2 1 2Total 77 4 61 81 137 238 230 122 950

MAT OF RODENT AND SHREW SERA Sera were collected from rodents and shrewsCaptured in Morogoro and surroundings.

For 2003 – 2004 a total of 1993 serum samples were collected.

Serum samples (n = 500) were randomly selected and testedby MAT against six serovars: Icterohaemorrhagiae, Grippotyphosa, Ballum, Canicola, Hardjo and Pomona (Table 5).

Serovars Icterohaemorrhagiae and Grippotyphosa were local isolates RM1and RM4 respectively (previously typed by KIT).

Highest MAT titre obtained (> 1:10240 ) was with serovar Icterohaemorrhagiae (RM1).

Table 5:MAT of rodents and shrews sera (n = 500) from Morogorotownship and surroundings

MAT Titres Ictero. Hardjo Pomona Canicola Ballum Gripo.

1:20 9 4 51:40 2 1 1 31:80 1 4 11:160 1 1 11:320 21:640 3 31:1280 3 11:2560 2>1:20480 2

Total (%) 25 (5) 0 1 (0.2) 14 (2.8) 0 10 (2)

SERA FROM DOMESTIC ANIMALS

Sera was obtained from dogs,cats and pigs (each 300 specimens) and from sheep and goats (total 300 sera).

Collection was done in urban and periurban Morogoro in the course of 2003. No further sampling was made in 2004.

Serology of the sera is yet to be carried out.

ISOLATION OF ZOONOTICS FROM ANIMALS (WP 3)

Isolation of Leptospira spp was from the urine and kidneys of captured rodents and shrews in FLETCHER and EMJH media.

Cultures were kept at RT (28–30 oC) and examinedfor leptospiral growth at an interval of one week over a period of 4 months.

Isolates were obtained from two rodent species (C.gambianus and M.natalensis) and from Crocidura spp (Table 6).

Other species of rodents: Arvicanthis spp (n=22), Nannomys spp(7) Tatera spp (9), Lemniscomis spp (4), Grammomys spp (13), Dasymys spp (6) Steatomys spp (1), Rattus spp (270) and Mus spp(137) gave no evidence of live leptospires.

Table 6: Leptospira isolates from rodents and shrews capturedin Morogoro

Rodent and shrew species

Total cultures

positive % Positive

M.natalensis 1112 7 0.69

Crocidura spp. 194 11 5.85

C.gambianus 190 9 4.74

TOTAL 1496 27 1.8

Cultures made in June, July, August and September (n =725) are still under investigation.

CHARACTERIZATION OF ISOLATES

Characterization shall start later in 2004/05.

Rabbits hyperimmune serum shall be raised to test the isolates.

Initially isolates shall be analysed by MAT against reference antisera.

Then PCR shall be applied to distinguish between saprophyticand pathogenic leptospires.

Cultures of the isolates shall subsequently be sent to KIT for confirmation.

SOIL AND WATER pH FROM TRAPPED SWAMPS IN MOROGORO

Soil and water samples were taken from collection sites and theirpH determined.

The distance between sample collection points ranged from 40-100m depending on the area size and site.

Most of collection sites had the pHs around neutral (Table 7).

Table 7: Soil and water pH of the trapping sites and corresponding leptospiral isolates

Trap site No of trappings

No of positive animals

Soil pH Water pH

Bigwa 3 10 6.93 6.80Kihonda 2 1 6.33 6.81Kilakala 2 5 7.20 7.26Mindu 1 1 7.14 6.75Kitungwa 3 0 6.94 7.02TANESCO 2 0 6.81 6.41Mjimwema 2 0 7.14 6.93Ngerengere 2 0 6.86 6.82Mazimbu 2 0 6.95 7.01

Kichangani 1 0 7.45 7.14

CONCLUSION

Leptospirosis is prevalent in Morogoro.

M. natalensis, C. gambianus and shrews are reservoirs.

Serovar Icterohaemorrhagiae appear most prevalent.

Humans appear to be infected predominantly by same serovar.

GENERAL CONSTRAINTS:

Delayed disbursement of funds for the second year of the projectactivities has impaired progress by:-●Delayed analysis of samples collected from domestic animals.●Delayed studies for the southern regions of Tanzania.

FUTURE PLANS:

Serology for leptospirosis toxoplasmosis in rodents, humans and animals in southern regions of Tanzania, including serological survey on toxoplasmosis.

Further characterization of rodents and leptospiral isolates obtained .

Repeat trapping in the swamps that have been trapped once.