Reduction in P. falciparum but not P. vivaxgenetic diversity post-LLIN
Based on the microsatellite haplotypes (n=860), the genetic diversity ofP. falciparum populations was modestly but significantly lower post-LLIN compared to the earlier time points for pre-LLIN populations (ESP1 and 2 2005 and MAD 2006). Mean heterozygosity for P. falciparum over all areas combined decreased significantly from 0.76±0.1 to 0.71±0.1 (Mann-Whitney U test p =0.036; Table S1) and allelic richness from 7.7±2.2 to 6.5±2.1 (Mann-Whitney U test p=0.014; Figure 2). These parameters also showed a small but insignificant decline for the provinces analysed individually (Figure 2, p>0.05). For P. vivax, overall genetic diversity remained high (post-LLIN Rs= 12.5; He =0.85, Table S1), but slightly different results were seen in each province (Figure 2, Table S1). In Madang Province after the distribution of LLINs, Hevalues slightly increased from 0.85±0.07 in 2006 to 0.88±0.04 in 2014 (p=0.3, Table S1), with high allelic richness (pre-LLIN Rs12.2±4.0 vs post-LLIN 14.0±3.4; p=0.2). Whereas in East Sepik Province,P. vivax genetic diversity decreased but not significantly withHe values of 0.83±0.09 to He 0.80±0.08 (2-sample t-test, p=0.48) and Rs values of 11.1±3.5 vs post-LLIN Rs 9.8±3.5 (2-sample t-test, p=0.33) (Table S1, Figure 2). No significant correlation was found between prevalence (by PCR) and heterozygosity, allelic richness, mean MOI, or proportion of multiple clone infections, for either species (data not shown).